Error Suppression

True-Q™ contains the following error suppression strategies:

1. Randomized Compiling (RC)

   A protocol which compiles circuits into a form where coherent noise is suppressed without adding depth to the circuit, that is, without increasing the number of cycles needed to implement the circuit. We provide the following examples that show how RC can be used in practice:

   • Example: Running Randomized Compiling

     Covers the fundamentals of how Randomized Compiling works in True-Q™

   • Example: Customizing Randomized Compiling with Cycle Markers

     Shows how RC can be customized to only act on specified cycles.

   • Example: Randomized Compilation with different Compilation Options

     Demonstrates more advanced features of RC, including its use with non-Clifford entangling gates, randomized measurements, and incorporating RC through explicit use of the Compiler rather than through the simple randomly_compile() interface.

   • Example: Randomly Compiling Arbitrary Multi-qudit Gates

     Demonstrates how to use the RCKak compiler pass to handle circuits containing non-Clifford multi-qudit gates without an additional decomposition step.

2. Stochastic Calibration (SC)

   A protocol based on cycle benchmarking, which allows users to diagnose how errors affect specific components of density operators.

   • Example: Running Stochastic Calibration

     Provides hands-on instructions on to how to implement stochastic calibration

3. Readout Calibration (RCAL)

   Diagnose state-dependent readout errors. The results can also be used to correct readout errors for other diagnostic tools.

   • Example: Running Readout Calibration

     Walks through the implementation of readout calibration for qubits and qutrits and shows how the correction can be automatically applied to a collection of circuits.

4. Noiseless Output Extrapolation (NOX)

   A protocol to extrapolate correct outputs from noisy circuits.

   • Example: Running Noiseless Output Extrapolation

     Shows how to mitigate the effects of noise afflicting circuits of qubits or qutrits by performing noiseless output extrapolation.