APS Physical Review Letters selects Station Q paper 

1 min read

  We are pleased to announce that the American Physical Society (APS) journal, Physical Review Letters, has selected the Station Q paper, Transport Signatures of Quasiparticle Poisoning in a Majorana Island, as an Editors’ Suggestion. The paper details how, working with theorists in Copenhagen, we found a way to measure the quasiparticle poisoning rate of a Majorana Read more

Magic state distillation with low space overhead and optimal asymptotic input count 

<1 min read

  In our quest for topological quantum computing with Majorana zero modes, one missing piece is the efficient, high-quality creation of magic states to perform the π/8 (or “T” gate). Our new paper, Magic State Distillation with Low Space Overhead and Optimal Asymptotic Input Count, provides a family of solutions to this need, allowing for a wide range Read more

Design automation and design space exploration for quantum computers 

1 min read

  A major hurdle for quantum algorithms for linear systems of equations, and for quantum simulation algorithms, is the difficulty to find simple circuits for arithmetic. Prior approaches typically led to a large overhead in terms of quantum memory, required operations, or implementation error. By leveraging recent advances in reversible logic synthesis, Martin Roetteler and Read more

Common framework for scientific experiments: QCoDeS 

1 min read

  QCoDeS is an open source data acquisition framework that was created by distilling the homegrown solutions used in Station Q’s experimental labs, and infused with all the best practices from the open source software world. It includes a simple syntax to define complex sweeps over n-dimensional parameter space, all the machinery required to visualize Read more

Transport signatures of quasiparticle poisoning in a Majorana island 

1 min read

As its name implies, the poisoning of Majorana devices by normal electrons is fatal to topological computation, so much effort is now focused on characterizing the degree of poisoning either by the creation of quasiparticle pairs within the device, or by electrons entering the device through the leads. A recent experiment (see https://arxiv.org/abs/1612.05748), led by Sven Read more

Anomalous Fraunhofer Interference in Epitaxial Superconductor-Semiconductor Josephson Junctions 

1 min read

  Last year saw a materials breakthrough, with the realization of a two-dimensional heterostructure combining superconductor and semiconductor layers. (See journals.aps.org/prb/abstract/10.1103/PhysRevB.93.15540.) Now, as shown in a recent report, this material has been used to study interference effects controlled by magnetic fields in a Josephson junction made from this material. Anomalous interference reveals properties of the semiconductor in Read more

Verified compilation of space-efficient reversible circuits 

1 min read

  Generation of reversible circuits from high-level code is an important problem in the compilation flow of quantum algorithms to lower-level hardware. The instantiation of quantum oracles in particular will require mapping classical circuits to a reversible implementation. Existing tools compile and optimize reversible circuits for various metrics, such as the overall circuit size or the Read more

Training a quantum optimizer 

<1 min read

  In this paper, published in Physical Review A, we show how to greatly improve success at solving Constraint Satisfaction Problems on a quantum computer by using a learned schedule, instead of the standard linear ramps. The technique actually improves as the problem gets larger and more difficult, allowing classical machines to learn optimizations that Read more

LIQUi| for quantum computing 

<1 min read

  LIQUi|> is a software architecture and tool suite for quantum computing. It includes a programming language, optimization and scheduling algorithms, and quantum simulators. LIQUi|> can be used to translate a quantum algorithm written in the form of a high-level program into the low-level machine instructions for a quantum device. LIQUi|> is developed by the Read more