Robin Blume-Kohout

Streaming universal distortion-free entanglement concentration (2009)

Blume-Kohout, Robin, Croke, Sarah, Gottesman, Daniel

This paper presents a streaming (sequential) protocol for universal entanglement concentration at the Shannon bound. Alice and Bob begin with N identical (but unknown) two-qubit pure states, each...

Gate fidelity fluctuations and quantum process invariants (2009)

Magesan, Easwar, Blume-Kohout, Robin, Emerson, Joseph

We characterize the quantum gate fidelity in a state-independent manner by giving explicit expressions for the variance and a method for calculating all moments of the gate fidelity. We discuss a...

Quantum Darwinism in Quantum Brownian Motion (2008)

Blume-KoHout, Robin, Zurek, Wojciech H.

Quantum Darwinism—the redundant encoding of information about a decohering system in its environment—was proposed to reconcile the quantum nature of our Universe with apparent classicality. We...

Characterizing the Structure of Preserved Information in Quantum Processes (2008)

Blume-Kohout, Robin, Ng, Hui Khoon, Poulin, David, Viola, Lorenza

We introduce a general operational characterization of information-preserving structures—encompassing noiseless subsystems, decoherence-free subspaces, pointer bases, and error-correcting...

The structure of preserved information in quantum processes (2007)

Blume-Kohout, Robin, Ng, Hui Khoon, Poulin, David, Viola, Lorenza

We introduce a general operational characterization of information-preserving structures (IPS) -- encompassing noiseless subsystems, decoherence-free subspaces, pointer bases, and error-correcting...

Quantum Darwinism in quantum Brownian motion: the vacuum as a witness (2007)

Blume-Kohout, Robin, Zurek, Wojciech H.

We study quantum Darwinism -- the redundant recording of information about a decohering system by its environment -- in zero-temperature quantum Brownian motion. An initially nonlocal quantum state...

Optimal, reliable estimation of quantum states (2006)

Blume-Kohout, Robin

Accurately inferring the state of a quantum device from the results of measurements is a crucial task in building quantum information processing hardware. The predominant state estimation procedure,...

Quantum Darwinism: Entanglement, branches, and the emergent classicality of redundantly stored quantum information (2006)

Blume-Kohout, Robin, Zurek, Wojciech H.

We lay a comprehensive foundation for the study of redundant information storage in decoherence processes. Redundancy has been proposed as a prerequisite for objectivity, the defining property of...

Accurate quantum state estimation via "Keeping the experimentalist honest" (2006)

Blume-Kohout, Robin, Hayden, Patrick

In this article, we derive a unique procedure for quantum state estimation from a simple, self-evident principle: an experimentalist's estimate of the quantum state generated by an apparatus should...

Quantum Darwinism: Entanglement, branches, and the emergent classicality of redundantly stored quantum information (2005)

Blume-Kohout, Robin, Zurek, W. H.

We lay a comprehensive foundation for the study of redundant information storage in decoherence processes. Redundancy has been proposed as a prerequisite for objectivity, the defining property of...

A simple example of "Quantum Darwinism": Redundant information storage in many-spin environments (2004)

Blume-Kohout, Robin, Zurek, Wojciech H.

As quantum information science approaches the goal of constructing quantum computers, understanding loss of information through decoherence becomes increasingly important. The information about a...

Physical-resource requirements and the power of quantum computation (2004)

Carlton M Caves, Robin Blume-kohout

doi:10.1088/1464-4266/6/8/027 The primary resource for quantum computation is the Hilbert-space dimension. Whereas Hilbert space itself is an abstract construction, the number of dimensions available...

Symmetric informationally complete quantum measurements (2004)

Renes, Joseph M., Blume-Kohout, Robin, Scott, Andrew James, Caves, Carlton M.

We consider the existence in arbitrary finite dimensions d of a positive operator valued measure (POVM) comprised of d2 rank-one operators all of whose operator inner products are equal. Such a set...

Symmetric Informationally Complete Quantum Measurements (2003)

Renes, Joseph M., Blume-Kohout, Robin, Scott, A. J., Caves, Carlton M.

We consider the existence in arbitrary finite dimensions d of a POVM comprised of d^2 rank-one operators all of whose operator inner products are equal. Such a set is called a ``symmetric,...

Exponential speed-up with a single bit of quantum information: Testing the quantum butterfly effect (2003)

Poulin, David, Blume-Kohout, Robin, Laflamme, Raymond, Ollivier, Harold

We present an efficient quantum algorithm to measure the average fidelity decay of a quantum map under perturbation using a single bit of quantum information. Our algorithm scales only as the...

Physical-resource demands for scalable quantum computation (2003)

Caves, Carlton M., Deutsch, Ivan H., Blume-Kohout, Robin

The primary resource for quantum computation is Hilbert-space dimension. Whereas Hilbert space itself is an abstract construction, the number of dimensions available to a system is a physical...

Decoherence from a Chaotic Environment: An Upside Down "Oscillator" as a Model (2002)

Blume-Kohout, Robin, Zurek, Wojciech H.

Chaotic evolutions exhibit exponential sensitivity to initial conditions. This suggests that even very small perturbations resulting from weak coupling of a quantum chaotic environment to the...

Compatibility of quantum states (2002)

Poulin, David, Blume-Kohout, Robin

We introduce a measure of the compatibility between quantum states--the likelihood that two density matrices describe the same object. Our measure is motivated by two elementary requirements, which...

Climbing Mount Scalable: Physical-Resource Requirements for a Scalable Quantum Computer (2002)

Blume-Kohout, Robin, Caves, Carlton M., Deutsch, Ivan H.

The primary resource for quantum computation is Hilbert-space dimension. Whereas Hilbert space itself is an abstract construction, the number of dimensions available to a system is a physical...

Climbing mount scalable: Physical resource requirements for a scalable quantum computer (2002)

Robin Blume-kohout, Carlton M. Caves, Ivan H. Deutsch

The primary resource for quantum computation is Hilbert-space dimension. Whereas Hilbert space itself is an abstract construction, the number of dimensions available to a system is a physical...