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Search Publications by: Yi-Kai Liu (Fed)

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Displaying 26 - 50 of 56

Experimentally Generated Random Numbers Certified by the Impossibility of Superluminal Signaling

April 11, 2018
Author(s)
Peter L. Bierhorst, Emanuel H. Knill, Scott C. Glancy, Yanbao Zhang, Alan Mink, Stephen P. Jordan, Andrea Rommal, Yi-Kai Liu, Bradley Christensen, Sae Woo Nam, Martin J. Stevens, Lynden K. Shalm
From dice to modern complex circuits, there have been many attempts to build increasingly better devices to generate random numbers. Today, randomness is fundamental to security and cryptographic systems, as well as safeguarding privacy. A key challenge

Quantifying the post-quantum security-margin of popular block ciphers

March 27, 2018
Author(s)
Yi-Kai Liu, Brittanney Amento-Adelmann, Markus Grassl, Brandon Langenberg, Eddie Schoute, Rainer Steinwandt
Mounting an exhaustive key search against a block cipher with Grover's algorithm requires the implementation of the target cipher on a quantum computer. We report quantum circuits and resource bounds for various block ciphers with different design

Thermodynamic Analysis of Classical and Quantum Search Algorithms

January 19, 2018
Author(s)
Ray A. Perlner, Yi-Kai Liu
We analyze the performance of classical and quantum search algorithms from a thermodynamic perspective, focusing on resources such as time, energy, and memory size. We consider two examples that are relevant to post-quantum cryptography: Grover's search

Phase Retrieval Using Unitary 2-Designs

September 4, 2017
Author(s)
Yi-Kai Liu, Shelby Kimmel
We consider a variant of the phase retrieval problem, where vectors are replaced by unitary matrices, i.e., the unknown signal is a unitary matrix U, and the measurements consist of squared inner products |Tr(C*U)|^2 with unitary matrices C that are chosen

Report on Post-Quantum Cryptography

April 28, 2016
Author(s)
Lidong Chen, Stephen P. Jordan, Yi-Kai Liu, Dustin Moody, Rene C. Peralta, Ray A. Perlner, Daniel C. Smith-Tone
In recent years, there has been a substantial amount of research on quantum computers - machines that exploit quantum mechanical phenomena to solve mathematical problems that are difficult or intractable for conventional computers. If large-scale quantum

Privacy Amplification in the Isolated Qubits Model

April 14, 2015
Author(s)
Yi-Kai Liu
Isolated qubits are a special class of quantum devices, which can be used to implement tamper-resistant cryptographic hardware such as one-time memories (OTM's). Unfortunately, these OTM constructions leak some information, and standard methods for privacy

Single-shot security for one-time memories in the isolated qubits model

August 21, 2014
Author(s)
Yi-Kai Liu
One-time memories (OTM's) are simple, tamper-resistant cryptographic devices, which can be used to implement sophisticated functionalities such as one-time programs. OTM's cannot exist in a fully-classical world, or in a fully-quantum world, but there is

Building one-time memories from isolated qubits

January 14, 2014
Author(s)
Yi-Kai Liu
One-time memories (OTM's) are a simple type of tamper-resistant cryptographic hardware, that can be used to implement many forms of secure computation, such as one-time programs. Here we investigate the possibility of building OTM's using "isolated qubits"

Multilingual Summarization: Dimensionality Reduction and a Step Towards Optimal Term Coverage

August 9, 2013
Author(s)
Yi-Kai Liu, John M. Conroy, Sashka T. Davis, Jeff Kubina, Dianne P. O'Leary, Judith D. Schlesinger
In this paper we present three term weighting approaches for multi-lingual document summarization and give results on the DUC 2002 data as well as on the 2013 Multilingual Wikipedia feature articles data set. We introduce a new interval-bounded nonnegative

Testing quantum expanders is co-QMA-complete

May 31, 2013
Author(s)
Yi-Kai Liu, Stephen P. Jordan, Pawel Wocjan, Adam Bookatz
A quantum expander is a unital quantum channel that is rapidly mixing, has only a few Kraus operators, and can be implemented efficiently on a quantum computer. We consider the problem of estimating the mixing time (i.e., the spectral gap) of a quantum