Chopped random-basis quantum optimization

@article{Caneva2011ChoppedRQ,
  title={Chopped random-basis quantum optimization},
  author={Tommaso Caneva and Tommaso Calarco and Simone Montangero},
  journal={Physical Review A},
  year={2011},
  volume={84},
  pages={022326}
}
In this work, we describe in detail the chopped random basis (CRAB) optimal control technique recently introduced to optimize time-dependent density matrix renormalization group simulations [P. Doria, T. Calarco, and S. Montangero, Phys. Rev. Lett. 106, 190501 (2011)]. Here, we study the efficiency of this control technique in optimizing different quantum processes and we show that in the considered cases we obtain results equivalent to those obtained via different optimal control methods while… 
Optimal control methods for quantum gate preparation: a comparative study
TLDR
From the numerical simulations, it is observed that GOAT achieves better results as compared to Krotov, GRAPE and CRAB, in terms of minimum infidelity, algorithmic simplicity and analyticity.
Global optimization for quantum dynamics of few-fermion systems
Quantum state preparation is vital to quantum computation and quantum information processing tasks. In adiabatic state preparation, the target state is theoretically obtained with nearly perfect
Quantum optimal control in a chopped basis: Applications in control of Bose-Einstein condensates
We discuss quantum optimal control of Bose-Einstein condensates trapped in magnetic microtraps. The objective is to transfer a condensate from the ground state to the first-excited state. This type
Quantum mechanics and speed limit of ultrafast local control in spin chains
We study optimization of fidelity for ultrafast transformation of a spin chain via external control of a local exchange coupling. We show that infidelity of such a process can be dramatically
Adiabatic population transfer of dressed spin states with quantum optimal control
We report theoretical studies of adiabatic population transfer using dressed spin states. Quantum optimal control using the algorithm of Chopped Random Basis (CRAB) has been implemented in a
Information theoretical analysis of quantum optimal control.
TLDR
It is shown that if an efficient classical representation of the dynamics exists, optimal control problems on many-body quantum systems can be solved efficiently with finite precision and one-dimensional slightly entangled dynamics can be efficiently controlled.
Hybrid optimization schemes for quantum control
TLDR
A two-stage optimization scheme to significantly speed up convergence and achieve simpler controls is proposed, showing that a combination of Nelder-Mead simplex and Krotov’s method yields considerably better results than either one of the two methods alone.
Quantum optimal control via gradient ascent in function space and the time-bandwidth quantum speed limit
A gradient ascent method for optimal quantum control synthesis is presented that employs a gradient derived with respect to the coefficients of a functional basis expansion of the control.
Push-Pull Optimization of Quantum Controls
TLDR
A stronger objective function which incorporates not only the target operator but also a set of its orthogonal operators is proposed, which finds significantly superior convergence of optimization routines with the combined influences of all the operators.
Quantum optimal control for pure-state preparation using one initial state
This paper presents a framework for solving the pure-state preparation problem using numerical optimal control. As an example, we consider the case where a number of qubits are dispersively coupled
...
...

References

SHOWING 1-10 OF 150 REFERENCES
Optimal control technique for many-body quantum dynamics.
We present an efficient strategy for controlling a vast range of nonintegrable quantum many-body one-dimensional systems that can be merged with state-of-the-art tensor network simulation methods
Quantum Optimally Controlled Transition Landscapes
TLDR
It is proved that for controllable quantum systems with no constraints placed on the controls, the only allowed extrema of the transition probability landscape correspond to perfect control or no control.
Quantum entanglement of excitons in coupled quantum dots
Optically controlled exciton dynamics in coupled quantum dots is studied. We show that the maximally entangled Bell states and Greenberger-Horne-Zeilinger (GHZ) states can be robustly generated by
A pseudospectral method for optimal control of open quantum systems.
TLDR
The Legendre pseudospectral method is applied to a series of optimal control problems on open quantum systems that arise in nuclear magnetic resonance spectroscopy in liquids and finds an excellent agreement between the maximum transfer efficiency and the analytical expressions.
Optimal control of coupled Josephson qubits
Quantum optimal control theory is applied to two and three coupled Josephson charge qubits. It is shown that by using shaped pulses a CNOT gate can be obtained with a trace fidelity > 0.99999 for the
Robust optimal quantum gates for Josephson charge qubits.
TLDR
The improvement in the gate performances discussed in this work (errors approximately 10(-3)-10(-4) in realistic cases) allows us to cross the fault tolerance threshold.
Quantum Ratchets for Quantum Communication with Optical Superlattices
We propose to use a quantum ratchet to transport quantum information in a chain of atoms trapped in an optical superlattice. The quantum ratchet is created by a continuous modulation of the optical
Preparation of decoherence-free cluster states with optical superlattices
We present a protocol to prepare decoherence-free cluster states using ultracold atoms loaded in a two dimensional superlattice. The superlattice geometry leads to an array of
Communication at the quantum speed limit along a spin chain
Spin chains have long been considered as candidates for quantum channels to facilitate quantum communication. We consider the transfer of a single excitation along a spin-1/2 chain governed by
Robust entanglement in antiferromagnetic Heisenberg chains by single-spin optimal control
We demonstrate how near-perfect entanglement (in fact arbitrarily close to maximal entanglement) can be generated between the end spins of an antiferromagnetic isotropic Heisenberg chain of length N,
...
...