Free-time and fixed end-point optimal control theory in quantum mechanics: application to entanglement generation.

We have constructed free-time and fixed end-point optimal control theory for quantum systems and applied it to entanglement generation between rotational modes of two polar molecules coupled by dipole-dipole interaction. The motivation of the present work is to solve optimal control problems more flexibly by extending the popular fixed time and fixed end-point optimal control theory for quantum systems to free-time and fixed end-point optimal control theory. As a demonstration, the theory that we have constructed in this paper will be applied to entanglement generation in rotational modes of NaCl-NaBr polar molecular systems that are sensitive to the strength of entangling interactions. Our method will significantly be useful for the quantum control of nonlocal interaction such as entangling interaction, which depends crucially on the strength of the interaction or the distance between the two molecules, and other general quantum dynamics, chemical reactions, and so on.

[1]  K. Yamashita,et al.  Partitioning of entangling interactions in terms of rotating wave approximation: An approach to the Bell state generation by laser fields , 2007 .

[2]  R. de Vivie-Riedle,et al.  Quantum computation with vibrationally excited molecules. , 2002, Physical review letters.

[3]  Orientations of two coupled molecules , 2004, quant-ph/0409155.

[4]  R. de Vivie-Riedle,et al.  The role of anharmonicity and coupling in quantum computing based on vibrational qubits , 2006 .

[5]  Stuart A. Rice,et al.  Optical Control of Molecular Dynamics , 2000 .

[6]  I. Chuang,et al.  Quantum Computation and Quantum Information: Introduction to the Tenth Anniversary Edition , 2010 .

[7]  Herschel Rabitz,et al.  Teaching lasers to control molecules in the presence of laboratory field uncertainty and measurement imprecision , 1993 .

[8]  Carmen M. Tesch,et al.  Applying optimal control theory for elements of quantum computation in molecular systems , 2001 .

[9]  Regina de Vivie-Riedle,et al.  Extensions to quantum optimal control algorithms and applications to special problems in state selective molecular dynamics , 1999 .

[10]  D. Babikov,et al.  Anharmonic properties of the vibrational quantum computer. , 2007, The Journal of chemical physics.

[11]  H. Rabitz,et al.  Transformations to diagonal bases in closed-loop quantum learning control experiments. , 2005, The Journal of chemical physics.

[12]  K. Yamashita,et al.  Ab initio study of optimal control of ammonia molecular vibrational wavepackets: Towards molecular quantum computing , 2005 .

[13]  D. Lauvergnat,et al.  Optimal control simulation of the Deutsch-Jozsa algorithm in a two-dimensional double well coupled to an environment. , 2007, The Journal of chemical physics.

[14]  R. de Vivie-Riedle,et al.  Vibrational molecular quantum computing: basis set independence and theoretical realization of the Deutsch-Jozsa algorithm. , 2004, The Journal of chemical physics.

[15]  H. Rabitz,et al.  Teaching lasers to control molecules. , 1992, Physical review letters.

[16]  R. Vivie-Riedle,et al.  Preparation and addressability of molecular vibrational qubit states in the presence of anharmonic resonance , 2003 .

[17]  D. Babikov Accuracy of gates in a quantum computer based on vibrational eigenstates. , 2004, The Journal of chemical physics.

[18]  T. Yokoyama,et al.  Quantitative analysis of long-range interactions between adsorbed dipolar molecules on Cu(111). , 2007, Physical review letters.

[19]  Paul Brumer,et al.  Laser control of product quantum state populations in unimolecular reactions , 1986 .

[20]  M. Horodecki,et al.  Inseparable Two Spin- 1 2 Density Matrices Can Be Distilled to a Singlet Form , 1997 .

[21]  Kosloff,et al.  Excitation without demolition: Radiative excitation of ground-surface vibration by impulsive stimulated Raman scattering with damage control. , 1992, Physical review letters.

[22]  K. Mishima,et al.  Quantum computing using molecular vibrational and rotational modes , 2007 .

[23]  Alex Brown,et al.  Quantum computing based on vibrational eigenstates: pulse area theorem analysis. , 2006, The Journal of chemical physics.

[24]  Eric G. Brown,et al.  Some Mathematical and Algorithmic Challenges in the Control of Quantum Dynamics Phenomena , 2002 .

[25]  K. Yamashita,et al.  Bell state generation of multi-level systems in the presence of complex entangling interactions , 2008 .

[26]  F. Remacle,et al.  Vibrational computing: simulation of a full adder by optimal control. , 2008, The Journal of chemical physics.

[27]  Toshiyuki Ohtsuka,et al.  A continuation/GMRES method for fast computation of nonlinear receding horizon control , 2004, Autom..

[28]  Charles H. Bennett,et al.  Purification of noisy entanglement and faithful teleportation via noisy channels. , 1995, Physical review letters.

[29]  H. Rabitz,et al.  RAPIDLY CONVERGENT ITERATION METHODS FOR QUANTUM OPTIMAL CONTROL OF POPULATION , 1998 .

[30]  B. Shore,et al.  Coherent population transfer among quantum states of atoms and molecules , 1998 .

[31]  H. Rabitz,et al.  Closing the Loop on Bond Selective Chemistry Using Tailored Strong Field Laser Pulses , 2002 .

[32]  Shlomo E. Sklarz,et al.  Quantum computation via local control theory : Direct sum vs. direct product Hilbert spaces , 2006 .

[33]  R. de Vivie-Riedle,et al.  Manganese pentacarbonyl bromide as candidate for a molecular qubit system operated in the infrared regime. , 2005, The Journal of chemical physics.

[34]  Samuel H. Tersigni,et al.  Wavepacket dancing: Achieving chemical selectivity by shaping light pulses , 1989 .

[35]  R. Vivie-Riedle,et al.  The role of phases and their interplay in molecular vibrational quantum computing with multiple qubits , 2006 .

[36]  Response to “Comment on ‘Anharmonic properties of the vibrational quantum computer’ ” [J. Chem. Phys. 128, 167101 (2008)] , 2008 .

[37]  D. Babikov,et al.  Phase control in the vibrational qubit. , 2006, The Journal of chemical physics.

[38]  Charles H. Bennett,et al.  Mixed-state entanglement and quantum error correction. , 1996, Physical review. A, Atomic, molecular, and optical physics.

[39]  K. Yamashita,et al.  Quantum computing using molecular electronic and vibrational states , 2008 .

[40]  Charles H. Bennett,et al.  Teleporting an unknown quantum state via dual classical and Einstein-Podolsky-Rosen channels. , 1993, Physical review letters.

[41]  D. Babikov,et al.  Coherent and optimal control of adiabatic motion of ions in a trap , 2008 .