Faculty Associate, Martin Kirk to Partner with CQuIC

CQuIC welcomes Distinguished University Professor Martin Kirk, of UNM Chemistry & Chemical Biology as a CQuIC Faculty Associate, effective August 12, 2019. Professor Kirk is a physical inorganic chemist and spectroscopist working on molybdenum enzymes, electronic structure contributions to molecular wire behavior, and the control of excited state processes. The quantum information science research being performed in his group is focused on the optical generation and manipulation of spin qubits in molecular systems. His research group employs a combined spectroscopic approach augmented by detailed bonding calculations to provide keen insight into the electronic structure of these novel transition metal – radical complexes, furthering our understanding of excited state lifetimes, excited state magnetic exchange interactions, and optical generation of entangled spin qubits. As an associate member of CQuIC, Professor Kirk looks forward to interactions and collaborations with the members of CQuIC.

CQuIC Welcomes Faculty Member, Susan Atlas

CQuIC welcomes Professor Susan Atlas, of UNM Physics and Astronomy as a CQuIC Faculty, effective August 12, 2019.

Professor Atlas is a theoretical chemical physicist working on electronic structure and atomic interactions, with particular emphasis on electron correlations, entanglement and chemical bonding, and the development of quantum-informed dynamical force fields for atomistic simulations.  She is interested in developing new algorithms for mapping quantum chemical methods onto emerging quantum computer architectures.  The research performed in her group is focused on understanding how quantum effects such as charge polarization and charge transfer impact the structure and properties of proteins and materials.  Her group is very interested in the study of natural molecular machines, intrinsically-disordered proteins, and non-equilibrium electron-atom dynamics.  As a faculty member in CQuIC, Professor Atlas looks forward to interactions and collaborations with other CQuIC faculty, postdocs, and students.

CQuIC Welcomes Faculty Member, Tameem Albash

CQuIC welcomes Professor Tameem Albash, of UNM Electrical and Computer Engineering (ECE), as a CQuIC Faculty, effective August 12, 2019.

Professor Albash is a theoretical physicist working on how and whether quantum advantages may manifest themselves in near-term quantum information processing hardware.  While quantum algorithms are known to provide computational speedups over their classical counterparts, current devices are limited both in the size and length of computations they can perform. The challenge is now to uncover computational tasks for which these and future near-term devices could provide measurable performance advantages given these constraints.  Of particular interest to his group is the question of whether there is ultimately a tradeoff between the noise-sensitivity of an algorithm and its ability of providing a genuine quantum speedup. As a faculty member in CQuIC, Professor Albash looks forward to interactions and collaborations with the members of CQuIC.

Optimized communication strategies with coherent states over phase noise channels

Optimized communication graphic illustration

The total amount of information that two parties can share is determined by the physical properties of the channel they are communicating over. Typically in optical communication, lasers are used to produce coherent states of light, and information can be encoded into either the phase, amplitude, or both. While the limits of information transfer over typical channels such as lossy optical fiber have been extensively studied, such limits in channels that also induce phase noise are not well understood, even though they are more realistic models for certain situations. When information is encoded into the phase of light, these channels severely degrade the amount of information that can be transmitted, especially when using conventional techniques of encoding and decoding, i.e. modulation and measurement.

This restriction of conventional approaches to optical communication lead us to propose and demonstrate methods for optimized communication strategies over such a phase-noise channel. The two key ingredients are finding particular physical states of light that can help shield information from the noise while keeping it easily extractable, and a novel coherent measurement based on counting single photons. These ingredients are optimized together for a specific noise channel in order to maximize the total amount of information transfer. This approach of a joint optimization allows for an increase in the amount of information that can be transmitted compared to conventional methods, even though the fundamental limits for the channel are not well known.

Reference information:

Optimized communication strategies with binary coherent states over phase noise channels

  1. T. DiMario, L. Kunz, K. Banaszek & F. E. Becerra

npj Quantum Information 5, 65 (2019)