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Introduction

Auspex, the automated system for python-based experiments, is a framework for performing laboratory measurements. Auspex was developed by a group that primarily performs measurements on superconducting qubits and magnetic memory elements, but its underpinnings are sufficiently general to allow for extension to arbitrary equipment and experiments. Using several layers of abstraction, we attempt to meet the following goals:

  1. Instrument drivers should be easy to write.

  2. Measurement code should be flexible and reusable.

  3. Data acquisition and processing should be asynchronous and reconfigurable.

  4. Experiments should be adaptive, not always pre-defined.

  5. Experiments should be concerned with information density, and not limited by the convenience of rectilinear sweeps.

A number of inroads towards satisfying points (1) and (2) are made by utilizing metaprogramming to reduce boilerplate code in Instrument drivers and to provide a versatile framework for defining an Experiment. For (3) we make use of the python asyncio library to create a graph-based measurement Filter pipeline through which data passes to be processed, plotted, and written to file. For (4), we attempt to mitigate the sharp productivity hits associated with experimentors having to monitor and constantly tweak the parameters of an Experiment. This is done by creating a simple interface that allows Sweeps to refine themselves based on user-defined criterion functions. Finally, for (5) we build in “unstructured” sweeps that work with parameter tuples rather than “linspace” style ranges for each parameter. The combination of (4) and (5) allows us to take beautiful phase diagrams that require far fewer points than would be required in a rectilinear, non-adaptive scheme.

Installation & Requirements

Auspex can be cloned from GitHub:

git clone https://github.com/BBN-Q/auspex.git

And subsequently installed using pip:

cd auspex
pip install -e .

Which will automatically fetch and install all of the requirements. If you are using an anaconda python distribution, some of the requirements should be install with conda install (like ruamel_yaml for example). The packages enumerated in requirements.txt are required by Auspex.

Qubit Experiments

Auspex is agnostic to the type of experiment being performed, but we include infrastructure for configuring and executing qubit experiments using the gate-level QGL language. In this case, auspex relies on bbndb as a database backend for sharing state and keeping track of configurations. Depending on the experiments being run, one may need to install a number of additional driver libraries.

If you’re running on a system with a low file descriptor limit you may see a ulimit error when trying to run or simulate experiments. This will look like a too many files error in python. This stems from ZMQ asynchronously opening and closing a large number of files. OSX has a default limit per notebook of 256 open files. You can easily change this number at the terminal before launching a notebook: ulimit -n 4096 or put this line in your .bash_prifile.

Genealogy and Etymology

Auspex is a synonym for an augur, whose role was to interpret divine will through a variety of omens. While most researchers rightfully place their faiths in the scientific method, it is not uncommon to relate to the roles of the augur. Auspex incorporates concepts from BBN’s QLab project as well as from the pymeasure project from Cornell University.

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