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Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
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Variational approach to quantum state tomography based on maximal entropy formalism
Rishabh Gupta1, Manas Sajjan1, Raphael D Levine2,3
1Department of Chemistry, Purdue University, West Lafayette, IN, USA.
Physical Chemistry Chemical Physics : PCCP
|November 25, 2022
Summary
This study introduces a maximal entropy approach for quantum state tomography, reconstructing quantum states from experimental data. The method yields a least-biased state, accurately replicating the experimentally prepared quantum state.
Area of Science:
- Quantum Information Science
- Quantum Computation
- Quantum State Tomography
Background:
- Quantum state tomography is crucial for validating quantum devices and reconstructing quantum states.
- Experimental data provides mean measurement values of operators, serving as input for state reconstruction.
Purpose of the Study:
- To develop a method for reconstructing quantum states with high fidelity using experimental data.
- To construct the least biased mixed quantum state consistent with measured expectation values.
Main Methods:
- Employing the maximal entropy formalism to construct a least-biased quantum state.
- Utilizing an informationally complete set of Hermitian operators for unique state specification.
- Reconstructing an effective Hamiltonian parameterized by Lagrange multipliers.
- Applying a hybrid quantum-classical variational algorithm with a parameterized quantum circuit for optimization.
Main Results:
- The formalism successfully reconstructs quantum states from expectation values.
- The method allows for the replication of the exact experimental quantum state within a tolerance.
- The variational optimization ensures convergence to the true quantum state.
Conclusions:
- The maximal entropy formalism provides a robust method for quantum state tomography.
- The proposed algorithm is implementable on near-term quantum devices.
- This approach enhances the validation and understanding of quantum systems.
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