PICA: Advanced High-Precision Transport Measurement Automation with Python

Open-source Python suite for laboratory instrument control and automation — GPIB/VISA & SCPI orchestration of Keithley, Keysight, Lakeshore, and Novocontrol instruments for cryogenic transport, resistivity, I-V, dielectric, and pyroelectric measurements.

Documentation: prathameshnium.github.io/PICA-Python-Instrument-Control-and-Automation · User Manual · PyPI · Install: pip install pica-suite

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v1.0.7: Linux install guide, Keithley 2400 memristor modules, C-V module v2, launcher module search and hover cards. Install or upgrade via pip: pip install --upgrade pica-suite

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Overview

High-precision, low-noise transport measurements are essential for advancing research in spintronics and materials characterisation. PICA (Python-based Instrument Control and Automation) is a modular, open-source software suite designed to automate advanced transport measurements for electronic devices and material samples. It runs on a standard Windows laboratory PC, and its installation, tests and windows are also verified on Linux.

PICA provides an extensible, unified graphical user interface (GUI) for orchestrating high-precision instruments — current source (DC/AC) units, nanovoltmeters, high resistance electrometers, impedance analysers, and temperature controllers such as the Keithley 6221, 2182, 2400, and 6517B, the Keysight E4980A LCR meter, the Lakeshore 350/340, the Cryo-con 34, and (experimentally) the Novocontrol Alpha-AN. Built on the robust Python scientific ecosystem (PyVISA, NumPy, pandas, Matplotlib), PICA drives these instruments together from one interface.

The suite performs automated protocols including:

• Temperature-dependent wide-range resistance measurement ($10^{-8}$ - $10^{16}$ Ω).
• Current-voltage (I-V) characterisation.
• Capacitance characterisation and magnetocapacitance studies (20 Hz - 2 MHz).
• Pyroelectric current measurement (resolution $10^{-15}$ A).

PICA Launcher v2. Quick Select picks a category, a module and a protocol, then launches that program; the status strip shows the temperature, the pressure (when a gauge is configured) and the result of the bus scan, read at startup and on Reload. This is Launcher v2 (python -m pica.main_v2); the 2.1.0 in its title is the launcher's own version, not the package version.

Advanced Options (Ctrl+Shift+A): every module PICA ships, grouped by measurement range and instrument, for when you already know which program you want. Hovering a row opens a card describing the measurement, its instruments and its inputs; Ctrl+F opens a search that finds any module by a few letters.

More details here: Full online documentation is available at https://prathameshnium.github.io/PICA-Python-Instrument-Control-and-Automation/. For usage guides, see the User Manual.

Table of Contents

• Overview
• What's New in v1.0.7
• Motivation
• Key Features
• Design and Implementation
• Supported Hardware Modules
• Utilities & Tools
• Demonstration of PICA (Screencast)
• Getting Started
  • Installing on Linux
• Running the Software (incl. Launcher v2 Quick Select and Advanced Options)
• System Requirements & Compatibility
• Running Tests Locally
• Project History
• Resources & Documentation
• Citation
• Authors & Funding
• License

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What's New in v1.0.7

v1.0.7 (October 2026) is the latest release, available on PyPI and GitHub Releases.

pip install pica-suite==1.0.7
# or upgrade from a previous version:
pip install --upgrade pica-suite

Highlights — changes since v1.0.6:

• Linux documentation: a Linux install guide (venv, tkinter, pyvisa-py, USB-TMC / serial / GPIB) and a "Linux report" issue template; running against real instruments on Linux is not yet verified.
• Memristor modules (Keithley 2400): switching I-V sweep, retention and endurance programs, plus a read-only Memristor Analysis utility.
• C-V module v2 (Keysight E4980A): rewritten sweep builder (bipolar, unipolar, ladder), bus-error retry and a separate event log.
• K6221 / 2182 I-V: custom list sweeps (paste from the List Maker), µA units and zero-crossing fixes.
• Launcher v2 updates: module search (Ctrl+F), hover cards in Advanced Options, View menu and an in-app viewer for the manual, README, change log and license.
• Packaging, CI & utilities: cleaner wheel, wider CI matrix (Python 3.10-3.13, Linux GUI smoke test), Quick Calc typesetting, Time Utility event log.

For the full changelog, see CHANGELOG.md.

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Motivation

Advancements in experimental physics and device manufacturing depend on the precise characterisation of material properties under extreme physical conditions. Researchers often face a binary choice: purchase expensive proprietary software or develop custom measurement scripts from scratch.

Libraries such as PyVISA and PyMeasure provide foundational drivers but leave users to write and maintain the measurement code. PICA builds on these libraries to offer a ready-to-run application. It provides a ready-to-run graphical interface that abstracts the underlying control logic, allowing experimentalists to focus on data acquisition without extensive software development overhead.

PICA enables continuous operation across a full range of measurements, from ultra-low resistance (with thermal offsets cancelled) to high-impedance, electrometric, pyroelectric and capacitance measurements, within a single framework.

Key Features

• Accessibility: A GUI launcher lets researchers without coding experience configure and run measurement protocols from pre-packaged modules.
• Operational Validation: Validated via cryogenic transport measurements using a custom-designed probe in conjunction with a Physical Property Measurement System (PPMS) (5-380 K, up to 14 Tesla) at the UGC DAE Consortium for Scientific Research, Mumbai Centre.
• Fault Tolerance: The launcher starts each measurement program in its own process, so a hardware timeout or driver crash in one program does not freeze the launcher or the other programs.
• CLI Templates: About fifteen measurements also have an Instrument_Control script (run from pica-cli) that can be adapted for headless automation or other workflows.
• Operational Transparency: PICA exposes real-time, time-stamped logs of what each module is doing (e.g., [10:05:25] Starting stabilization process...). This aids debugging, ensures scientific reproducibility, and allows verification of measurement protocols.
• Open Source Extensibility: Researchers can integrate new instrument drivers or experimental protocols by copying the closest existing module and changing its SCPI commands. Every module is a single self-contained file, so a new one does not touch the others.

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Design and Implementation

PICA is built on a modular architecture characterised by self-contained modules, so adding a module cannot break the others.

Process Isolation and Concurrency

The launcher starts every measurement program in its own process with Python's standard multiprocessing library.

• Stability: If an instrument hangs, only that program's process is affected. It can be closed without freezing the launcher or the other open programs, and data already written stays on disk.
• Responsiveness: The tkinter-based frontend remains responsive for live matplotlib data plotting even while the backend waits for hardware triggers.
• Data Integrity: Each data point is appended to the file as soon as it is measured, so a crash or power cut loses at most the point in progress.

Hardware Abstraction Layer

PICA utilizes PyVISA to abstract low-level communication protocols (GPIB, USB, Ethernet). The software implements a strict initialization routine:

1. Connection Verification: A built-in "VISA Instrument Scanner" queries the bus (*IDN?) to map instrument addresses.
2. Instrument Reset: Modules that control an instrument reset it (*RST / *CLS) to a known state; read-only sensing modules never write to the thermometer.
3. Shutdown: On finish, Stop, error or window close, sources are switched off and heaters set to off.

Testing and Simulation

PICA includes a testing suite using pytest and unittest.mock to simulate VISA resources, allowing verification of backend logic streams and command sequences without constant access to physical instruments.

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Supported Hardware Modules

These modules drive the following hardware. The ranges are those of the instruments, together spanning 24 orders of magnitude in resistance.

Module	Configuration / Instrument	Use Case	Range
Ultra Low Resistance Measurements	Keithley 6221 + K2182 + Lakeshore 350/340	Superconductors & metallic films; cancels thermal EMFs by current reversal (Keithley Delta mode).	10 nΩ - 100 MΩ
Mid-Resistance (Standard)	Keithley 2400 SourceMeter + Lakeshore 350/340	Semiconductors, oxides, general transport.	100 µΩ - 200 MΩ
Mid-Resistance (High-Precision)	Keithley 2400 + K2182 + Lakeshore 350/340	Detecting subtle phase transitions.	1 µΩ - 100 MΩ
High-Resistance	Keithley 6517B Electrometer + Lakeshore 350/340	High bandgap materials, polymers, & ceramics.	1 Ω - 10 PΩ
Capacitance Analysis	Keysight E4980A + Lakeshore 350/340	C-V Analysis and Magnetocapacitance characterisation.	20 Hz - 2 MHz
Pyroelectric	K6517B + Lakeshore 350/340	Current vs Temp (detecting Curie temperature).	$10^{-15}$ A Resolution
Broadband Dielectric Spectroscopy (experimental)	Novocontrol Alpha-AN + ZG4 interface	Frequency-domain dielectric & impedance spectroscopy with WinDETA-compatible exports.	20 Hz - 10 MHz
AC Transport (experimental)	Keithley 6221 + SR830 lock-in or Keithley 197A	Four-probe AC I-V, frequency scan and R-T.
Memristor Switching (v1.0.7)	Keithley 2400	Switching I-V, retention and endurance of resistive-switching devices.	±200 V source, compliance set per run

Each module drives specific instruments; adapting one to a similar model usually means editing its SCPI commands.

Advanced Temperature Step Control (Lakeshore 350)

pica/lakeshore/T_Control_L350_Step_GUI_advanced.py is a self-contained, advanced version of the classic step-sequence controller (T_Control_L350_Step_GUI.py, which remains unchanged for existing workflows). It embeds the field-tested v1.2 stabilization logic (two-stage approach, rolling-window tolerance + drift criterion, stabilization timeout) and adds:

• Adaptive ramp rate — the rate is computed per step as |ΔT| × Step Factor, then hard-capped by an editable low-temperature table (77:0.3, 100:0.5, else:5 = max 0.3 K/min below 77 K, 0.5 K/min below 100 K, otherwise 5 K/min). This suppresses the large overshoot seen below 100 K on LN2-dewar probes, where even a small heater input raises the temperature substantially. The first setpoint of a run is approached extra slowly (First-Step ×, default 0.5). Untick Adaptive ramp rate to use a fixed manual rate.
• Approach from one side — optional "always from below/above" mode for hysteresis-sensitive measurements: the slow final ramp always enters the setpoint from the chosen side.
• Stability criteria — configurable ±tolerance band, rolling window length, drift limit (K/min), and a max-wait timeout with a loud warning if stabilization fails.
• Safety — hardcoded 340 K kill switch, user-set soft Max-Temp limit with graceful abort (ramp stopped, heater off), heater-range checks, and crash-safe shutdown on window close or error.
• Run control & logging — Pause/Resume, Skip Step, live-editable sequence, per-poll CSV (with ramp rate + phase columns), a per-setpoint summary CSV (rate used, stabilization time, outcome), and a live plot showing the setpoint and its tolerance band. After each stabilization the program beeps and waits for the Proceed button (external-measurement handshake).

The combined dielectric-scan program pica/keysight/Step_Frequency_Scan_E4980A_GUI.py carries the same advanced control set — adaptive ramp rate, approach-from-one-side, Pause/Skip, soft Max-Temp limit, tolerance band, and stabilization-summary CSV — as an embedded copy (every PICA program stays self-contained). Being an unattended overnight program, on stabilization timeout it logs a loud warning and proceeds with the frequency sweep instead of waiting.

Module Previews

R-T measurement interface using the K6221/2182 for low-resistance samples, employing the Ultra Low Resistance Measurement technique to cancel thermal EMFs.

Interface for current-voltage (I-V) characterisation of high-impedance materials using the Keithley 6517B Electrometer.

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Utilities & Tools

Beyond the measurement modules, PICA ships a growing set of standalone laboratory utilities, all accessible from the launcher:

• VISA Instrument Scanner — queries the GPIB/USB/Ethernet bus (*IDN?) to map connected instrument addresses.
• PICA Plotter Utility — multi-file data plotting for comparison and analysis during or after measurements.
• SCPI Console (v1.0.6) — interactive terminal for sending raw SCPI commands to any VISA instrument.
• PPMS helper utilities (v1.0.6) — plotter, sequence visualizer, and time estimator for Quantum Design PPMS workflows.
• Calculators & helpers — List Maker, Quick Calc, unit converter, MD-ratio calculator, PID simulator, Time Utility and the read-only Memristor Analysis (v1.0.7).

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Demonstration of PICA (Screencast)

A screencast demonstrating the high resistance IV module is available at this link.

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Pre-requisites: The VISA Driver

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Getting Started

PICA is available on PyPI and structured as a standard Python package. Options 1 and 2 are for Windows, the platform PICA is validated on in the lab. For Linux, see Option 3.

Option 1: Install from PyPI (Recommended)

pip install pica-suite

To upgrade to the latest version (currently v1.0.7):

pip install --upgrade pica-suite

Option 2: Install from Source

1. Clone the Repository

   git clone https://github.com/prathameshnium/PICA-Python-Instrument-Control-and-Automation.git
   cd PICA-Python-Instrument-Control-and-Automation
   

2. Create Virtual Environment & Install

   # Create and activate a virtual environment
   python -m venv venv
   venv\Scripts\activate
   
   # Install the package and its dependencies
   pip install .
   

   To update PICA to the latest version, run the following command in the project directory:

   pip install --upgrade .
   

   If you are already in your virtual environment and want to force Python to reinstall the package (overwriting the old one), run this in your root project folder:

   pip install --force-reinstall .
   

3. Development install (for contributors)

   To work on PICA itself, install it in editable mode together with the test and lint tools. Edits to the source then take effect without reinstalling:

   pip install -e .
   pip install -r requirements-dev.txt
   

   Then run the test suite to confirm the setup (see Running Tests Locally):

   pytest
   

   Note: Ensure you have the NI-VISA drivers installed on your host machine to allow PyVISA to communicate with the hardware.

Option 3: Installing on Linux

What has been checked:

Check	Ubuntu 24.04, CI on every push (full suite on Python 3.10, GUI smoke test on 3.13)	Ubuntu 26.04, Python 3.14 (manual)
pip install	Yes	Yes
Test suite (mocked instruments)	Yes	Yes
Programs in the launcher, plus both launchers, open	Yes, real Tk windows under xvfb (tests/test_gui_windows_open_for_real.py); all except the 32-bit Alpha-AN scan, see below	Yes, same exception
Measurement against real instruments	No, not yet verified	No, not yet verified

1. Install the system packages. Tkinter and the emoji font are usually not part of a minimal install. Without the font, the icons on buttons show as empty boxes.

# Debian / Ubuntu
sudo apt install python3-venv python3-tk fonts-noto-color-emoji

# Fedora
sudo dnf install python3-tkinter google-noto-color-emoji-fonts

# Arch
sudo pacman -S tk noto-fonts-emoji

2. Create a virtual environment and install PICA.

python3 -m venv ~/pica-venv
source ~/pica-venv/bin/activate
pip install pica-suite

3. Set up a VISA backend. On Linux, PICA uses the pure-Python pyvisa-py backend, which pip install pica-suite installs for you. Each kind of connection needs one extra piece:

Connection	What you need
Ethernet (LAN / VXI-11 / raw socket)	Nothing extra
Serial (RS-232 / USB-serial adapter)	Nothing extra (pyserial is installed with PICA, via PyMeasure)
USB (USB-TMC instruments)	pip install pyusb, plus a udev rule giving your user access to the device (pyvisa-py docs)
GPIB card	The linux-gpib kernel driver for your card, then pip install "pica-suite[gpib]"

NI-VISA also exists for Linux, but only for a few distributions. See NI's Linux support page.

To use serial ports, your user must be in the dialout group. Log out and back in after running this:

sudo usermod -aG dialout $USER

Check that the backend sees your instruments:

pyvisa-info
python -c "import pyvisa; print(pyvisa.ResourceManager('@py').list_resources())"

4. Run PICA. Start it the same way as on Windows (see Running the Software):

pica-gui

Differences from Windows:

• Sleep during overnight runs. On Windows, the long unattended programs (the E4980A temperature, frequency and PPMS scans, the Cryo-con 34 R-T modules and the pressure logger) stop the PC from sleeping during a run; other modules do not. On Linux none can, so block sleep yourself, for example by launching PICA through systemd-inhibit:

  systemd-inhibit --what=idle:sleep --why="PICA measurement" pica-gui
  

• Alert sounds. Most modules fall back to the system bell on Linux for the end-of-run and alarm beeps, and it may be muted. The three Keithley 2400 memristor modules beep only on Windows and are silent on Linux. The on-screen banners and logs still appear.
• Different fonts. Linux draws the windows with its default fonts, usually DejaVu. The layout is the same, but the text is slightly wider.
• Windows-only modules. The 32-bit Novocontrol Alpha-AN frequency scan and the 32-bit GPIB scanner call Windows' gpib-32.dll directly, so they will not work on Linux. The 32-bit Alpha-AN scan does not open its window: it shows a "No GPIB driver" error and exits. The 32-bit GPIB scanner opens but reports that the driver is Windows-only. The regular Alpha-AN module goes through VISA and is not affected.

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Running the Software

1. Graphical Launcher (Recommended) The central dashboard for accessing all modules, the plotter, and the scanner.

   pica-gui
   

   You can also run any of the individual GUI measurement modules independently. This is useful for quickly accessing a specific measurement without opening the main launcher. To do this, simply run the Python script for the desired module. For example:

   python -m pica.keithley.k6517b.High_Resistance.IV_K6517B_GUI
   

2. Launcher v2 (in testing) A second launcher that opens on a Quick Select screen — category, module and protocol, each explained in plain language — and keeps the full module grid in an Advanced Options window (Ctrl+Shift+A). The status strip carries the temperature and a button opening Instrument Status: every instrument with its light, anything new on the bus named from its *IDN? reply, and the VISA/GPIB scan table.

   python -m pica.main_v2
   

   This works after pip install pica-suite. From a source checkout, python run_pica_v2.py does the same. pica-gui always opens the classic launcher.

   Find any program fast: Advanced Options and Search

   Shortcut	Opens
   Ctrl+Shift+A (or View menu)	Advanced Options: every module PICA ships on one screen, nothing filtered
   Ctrl+F (or View > Search Modules)	Search: fuzzy search over every program PICA can start

   Advanced Options is the expert route. Use it when you already know which program you want, or need one that Quick Select does not list:

   • the Cryo-con 34 and Lakeshore 340 twins of most programs
   • the standalone temperature utilities
   • the Novocontrol Alpha-AN and the bench multimeter

   Rest the pointer on a module row and a card shows what it measures, which instruments it opens and what it will ask for.

   Search works from either window and matches names, instruments, descriptions and input fields: try k2400 rt, cc34, butterfly, or even a misspelt resistence. Results list instruments first (Keithley 2400 — I-V Sweep); press Enter to launch.

3. Command Line Interface (CLI) For headless operation, without the GUI.

   pica-cli
   

System Requirements & Compatibility

Platforms:

• Windows 10 / 11 (x86_64): fully supported, and used daily in the lab with real instruments.
• Linux: installation, tests and GUIs verified, but measurements against real instruments not yet verified. See Option 3: Installing on Linux.
• macOS: not tested.

Example Usage: Running a Measurement

Upon launching PICA (pica-gui), select your desired measurement module from the main dashboard. Each module opens as a single window divided into two panels:

1. Configuration (Control Panel - Left):

   • Setup: Widen this panel first to view all experimental parameters.
   • Parameters: Specify the Sample Name, select the File Storage Location, and choose the Instrument Address (GPIB/VISA) via the dropdown selection box.
   • Protocol: Define measurement specific settings such as voltage/current limits, temperature step sizes, and delay times.
   • Console: A scrollable log at the bottom provides a continuous, time-stamped stream of all operations and SCPI commands sent to the instruments.

2. Visualization (Plot Panel - Right):

   • Real-Time Monitoring: Displays up to four simultaneous plots (e.g., Resistance vs. Temperature, Voltage vs. Current) updated in real-time.
   • Data Analysis: Includes options to switch axes to logarithmic scales for better visualization of wide-range data.
   • Utilities: Two icon buttons in the header bar provide instant access to:
     • VISA Instrument Scanner: To verify instrument connections and addresses.
     • PICA Plotter Utility: For comparing and analysing data during or after a measurement.

The interface is designed to be minimalistic to reduce unnecessary user interaction during active high-precision, low-noise transport measurements.

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Running Tests Locally

Test coverage: the suite has 3,500+ tests, all run against mocked VISA instruments, so no hardware is needed. They cover 34% of the statements in pica/ (measured 2026-10-17 with --cov=pica, v1.0.7). The Codecov badge measures the whole repository, so its figure differs.

To run the test suite locally, first install the development dependencies:

pip install -r requirements-dev.txt

Then, you can run the tests:

python -B -m pytest -p no:cacheprovider

How to Check Coverage Locally

To see the coverage percentage on your local machine, run this command instead:

python -B -m pytest --cov=pica --cov-report=term-missing -p no:cacheprovider

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Project History

For downloadable release builds, please visit the releases page.

PICA evolved from simple offline scripts in 2022 to a full-stack automated suite.

• v1.0.7 (Latest): Linux install guide and issue template, Keithley 2400 memristor sweep / retention / endurance modules with a read-only analysis utility, C-V module v2, K6221/2182 custom-list I-V, launcher module search and hover cards, cleaner wheel. Available on PyPI.
• v1.0.6: Advanced Lakeshore step control (adaptive ramp rates, low-temperature safety caps), Cryo-con 34 and Lakeshore 340 support, AC resistivity (SR830 / 197A), PPMS dielectric master protocol, Novocontrol Alpha-AN (experimental), I-V fixes, launcher v2, diagnostic tools and new utilities. Available on PyPI.
• v1.0.5: E4980A frequency and temperature scan programs, Lakeshore 350 direct and step control, K6517B poling, new utilities (P-E plotter, calculators, unit converter) and core fixes.
• v1.0.4: Documentation infrastructure release — Read the Docs integration, preprint page with automated PDF build, and CI/CD workflow updates.
• v1.0.3: GUI refreshed with the Latte theme — lighter, warmer, and less dark. First release published to PyPI.
• v1.0.1 / v1.0.0 (Initial Public Release): Version numbering was reset from legacy development builds (v17.0) to v1.0.0 to standardize the package for public distribution and citation.
• v17.0: Professional directory restructuring, Semantic Versioning, and documentation overhaul.
• v15.0: JOSS submission preparation, CI/CD integration.
• v13.0: Transition to Multiprocessing and standardized GUI themes.

The project's earlier history and foundational development are outlined below:

2022 - 2023: Inception & Prototyping

• 2023 (Migration): Moved from offline lab systems to GitHub; organized scripts into instrument modules (Keithley/Lake Shore).
• 2022 (Origins): Started in an air-gapped lab with pyvisa scripts replacing manual logging.
  • Concept: Proposed by Dr. Sudip Mukherjee to automate characterisation workflows.
  • Prototypes: Built alongside hardware upgrades and cryogenic probe work at UGC-DAE CSR.

Background: For a detailed chronological log, see CHANGELOG.md.

Resources & Documentation

• Online Documentation: Full documentation site at https://prathameshnium.github.io/PICA-Python-Instrument-Control-and-Automation/.
• PyPI Package: Install directly via https://pypi.org/project/pica-suite/.
• User Manual: Details on the project and usage guides are available in the User Manual.
• Instrument Manuals: A list of instrument manuals is available in docs/Instruments_Manuals_Lists.md.
• Novocontrol GPIB Runbook: Setup and troubleshooting guide for the Alpha-AN analyzer over GPIB in docs/Novocontrol_GPIB_Runbook.md.
• GitLab Backup: This project is manually backed up weekly to a GitLab repository.
• Project Web Page: https://prathameshdeshmukh.site/pages/project-pica.html.
• Preprint: Access the full preprint and related materials at https://prathameshnium.github.io/PICA-Python-Instrument-Control-and-Automation/publications/ or download the PDF directly (alternate link at Academia.edu).

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Citation

If you use this software in your research, please cite it:

@software{Deshmukh_PICA_2026,
  author       = {Deshmukh, Prathamesh Keshao and Mukherjee, Sudip},
  title        = {{PICA: Advanced High-Precision Transport Measurement Automation with Python}},
  month        = oct,
  day          = 17,
  year         = 2026,
  publisher    = {Zenodo},
  version      = {1.0.7},
  doi          = {10.5281/zenodo.18377216},
  url          = {https://doi.org/10.5281/zenodo.18377216}
}

Authors & Funding

This project is led by Prathamesh Deshmukh under the supervision of Dr. Sudip Mukherjee at the UGC-DAE Consortium for Scientific Research, Mumbai Centre, Bhabha Atomic Research Centre, Mumbai, 400 085, Maharashtra, India.

We acknowledge the financial support provided under the SERB-CRG project grant No. CRG/2022/005676 from the Anusandhan National Research Foundation (ANRF), a statutory body of the Department of Science and Technology (DST), Government of India.

License

This project is licensed under the MIT License - see the LICENSE file for details.

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_{Keywords: Python instrument control · laboratory automation · GPIB · PyVISA · SCPI · VISA · Keithley 2400 SourceMeter · Keithley 6221 current source · Keithley 2182 nanovoltmeter · Keithley 6517B electrometer · Keysight E4980A LCR meter · Lakeshore 350 temperature controller · Novocontrol Alpha-AN · broadband dielectric spectroscopy · PPMS · cryogenics · transport measurements · resistivity vs temperature · I-V characterization · delta mode · magnetocapacitance · pyroelectric current · condensed matter physics · materials characterization}