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Search Publications by: Yi-Kai Liu (Fed)

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Displaying 1 - 25 of 27

Status Report on the First Round of the Additional Digital Signature Schemes for the NIST Post-Quantum Cryptography Standardization Process

October 24, 2024
Author(s)
Gorjan Alagic, Maxime Bros, Pierre Ciadoux, David Cooper, Quynh Dang, Thinh Dang, John M. Kelsey, Jacob Lichtinger, Carl A. Miller, Dustin Moody, Rene Peralta, Ray Perlner, Angela Robinson, Hamilton Silberg, Daniel Smith-Tone, Noah Waller, Yi-Kai Liu
The National Institute of Standards and Technology is in the process of evaluating public-key digital signature algorithms through a public competition-like process for potential standardization. Any signature scheme eventually selected would augment

Post-Quantum Cryptography, and the Quantum Future of Cybersecurity

April 9, 2024
Author(s)
Yi-Kai Liu, Dustin Moody
We review the current status of efforts to develop and deploy post-quantum cryptography on the Internet. Then we suggest specific ways in which quantum technologies might be used to enhance cybersecurity in the near future and beyond. We focus on two goals

Lower Bounds on Quantum Annealing Times

April 5, 2023
Author(s)
Luis Pedro Garcia-Pintos, Lucas Brady, Jacob Bringewatt, Yi-Kai Liu
The adiabatic theorem provides sufficient conditions for the time needed to prepare a target ground state. While it is possible to prepare a target state much faster with more general quantum annealing protocols, rigorous results beyond the adiabatic

Status Report on the Third Round of the NIST Post-Quantum Cryptography Standardization Process

September 29, 2022
Author(s)
Gorjan Alagic, Daniel Apon, David Cooper, Quynh Dang, Thinh Dang, John M. Kelsey, Jacob Lichtinger, Yi-Kai Liu, Carl A. Miller, Dustin Moody, Rene Peralta, Ray Perlner, Angela Robinson, Daniel Smith-Tone
The National Institute of Standards and Technology is in the process of selecting public-key cryptographic algorithms through a public, competition-like process. The new public-key cryptography standards will specify additional digital signature, public

Status Report on the Third Round of the NIST Post-Quantum Cryptography Standardization Process

July 5, 2022
Author(s)
Gorjan Alagic, David Cooper, Quynh Dang, Thinh Dang, John M. Kelsey, Jacob Lichtinger, Yi-Kai Liu, Carl A. Miller, Dustin Moody, Rene Peralta, Ray Perlner, Angela Robinson, Daniel Smith-Tone, Daniel Apon
The National Institute of Standards and Technology is in the process of selecting public-key cryptographic algorithms through a public, competition-like process. The new public-key cryptography standards will specify additional digital signature, public

Status Report on the Second Round of the NIST Post-Quantum Cryptography Standardization Process

July 22, 2020
Author(s)
Dustin Moody, Gorjan Alagic, Daniel C. Apon, David A. Cooper, Quynh H. Dang, John M. Kelsey, Yi-Kai Liu, Carl A. Miller, Rene C. Peralta, Ray A. Perlner, Angela Y. Robinson, Daniel C. Smith-Tone, Jacob Alperin-Sheriff
The National Institute of Standards and Technology is in the process of selecting one or more public-key cryptographic algorithms through a public, competition-like process. The new public-key cryptography standards will specify one or more additional

Classifying single-qubit noise using machine learning

August 30, 2019
Author(s)
Travis L. Scholten, Yi-Kai Liu, Kevin Young, Robin Blume-Kohout
As quantum information processors (QIPs) grow more sophisticated, characterizing their behavior becomes harder. Larger QIPs have more properties that need to be characterized, and inventing a new quantum characterization, verification, and validation (QCVV

Status Report on the First Round of the NIST Post-Quantum Cryptography Standardization Process

January 31, 2019
Author(s)
Gorjan Alagic, Jacob M. Alperin-Sheriff, Daniel Apon, David Cooper, Quynh H. Dang, Carl Miller, Dustin Moody, Rene Peralta, Ray Perlner, Angela Robinson, Daniel Smith-Tone, Yi-Kai Liu
The National Institute of Standards and Technology is in the process of selecting one or more public-key cryptographic algorithms through a public competition-like process. The new public- key cryptography standards will specify one or more additional

Recovering quantum gates from few average gate fidelities

October 24, 2018
Author(s)
Yi-Kai Liu, Ingo Roth, Richard Kueng, Shelby Kimmel, David Gross, Jens Eisert, Martin Kliesch
Characterizing quantum processes is a key task in and constitutes a challenge for the development of quantum technologies, especially at the noisy intermediate scale of today's devices. One method for characterizing processes is randomized benchmarking

Pseudorandom Quantum States

August 19, 2018
Author(s)
Yi-Kai Liu, Zhengfeng Ji, Fang Song
We propose the concept of pseudorandom quantum states, which appear random to any quantum polynomial-time adversary. It offers a computational approximation to perfectly random quantum states (analogous to cryptographic pseudorandom generators), as opposed

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