English
Related papers

Related papers: Depth-2 QAC circuits cannot simulate quantum parit…

200 papers

We present an indirect two-qubit parity meter in planar circuit quantum electrodynamics, realized by discrete interaction with an ancilla and a subsequent projective ancilla measurement with a dedicated, dispersively coupled resonator.…

Mesoscale and Nanoscale Physics · Physics 2014-03-07 O. -P. Saira , J. P. Groen , J. Cramer , M. Meretska , G. de Lange , L. DiCarlo

One of the most exciting quantum emulation [1] breakthroughs was the first analog signal-based emulation of a universal quantum computer [2]. This yielded a very interesting paper, but no practical use - even for theorists. The reason for…

Quantum Physics · Physics 2023-02-03 Marcus Edwards

We present a native three-qubit entangling gate that exploits engineered interactions to realize control-control-target and control-target-target operations in a single coherent step. Unlike conventional decompositions into multiple…

Quantum Physics · Physics 2025-08-15 Xuexin Xu , Siyu Wang , Radhika Joshi , Rihan Hai , Mohammad H. Ansari

Random unitaries are a central object of study in quantum information, with applications to quantum computation, quantum many-body physics, and quantum cryptography. Recent work has constructed unitary designs and pseudorandom unitaries…

Quantum Physics · Physics 2025-09-29 Ben Foxman , Natalie Parham , Francisca Vasconcelos , Henry Yuen

While all quantum algorithms can be expressed in terms of single-qubit and two-qubit gates, more expressive gate sets can help reduce the algorithmic depth. This is important in the presence of gate errors, especially those due to…

The paper discusses the asymptotic depth of a reversible circuit consisting of NOT, CNOT and 2-CNOT gates. Reversible circuit depth function $D(n, q)$ for a circuit implementing a transformation $f\colon \mathbb Z_2^n \to \mathbb Z_2^n$ is…

Emerging Technologies · Computer Science 2016-02-16 Dmitry V. Zakablukov

Two-qubit interactions are at the heart of quantum information processing. For single-spin qubits in semiconductor quantum dots, the exchange gate has always been considered the natural two-qubit gate. The recent integration of magnetic…

Mesoscale and Nanoscale Physics · Physics 2015-05-20 T. Meunier , V. E. Calado , L. M. K. Vandersypen

Equivalence checking of quantum circuits is an essential element in quantum program compilation, in which a quantum program can be synthesized into different quantum circuits that may vary in the number of qubits, initialization…

Quantum Physics · Physics 2024-04-19 Tian-Fu Chen , Jie-Hong R. Jiang , Min-Hsiu Hsieh

In order to formally understand the power of neural computing, we first need to crack the frontier of threshold circuits with two and three layers, a regime that has been surprisingly intractable to analyze. We prove the first super-linear…

Computational Complexity · Computer Science 2018-02-01 Daniel M. Kane , Ryan Williams

We present two protocols for classical verification of quantum depth. Our protocols allow a purely classical verifier to distinguish devices with different quantum circuit depths even in the presence of classical computation. We show that a…

Quantum Physics · Physics 2022-05-11 Nai-Hui Chia , Shih-Han Hung

Entangling gates between qubits are a crucial component for performing algorithms in quantum computers. However, any quantum algorithm must ultimately operate on error-protected logical qubits encoded in high-dimensional systems. Typically,…

Quantum algorithm design usually assumes access to a perfect quantum computer with ideal properties like full connectivity, noise-freedom and arbitrarily long coherence time. In Noisy Intermediate-Scale Quantum (NISQ) devices, however, the…

Quantum Physics · Physics 2020-09-11 Xiangzhen Zhou , Sanjiang Li , Yuan Feng

Let $\eta_0$ be the supremum of those $\eta$ for which every poly-size quantum circuit can be simulated by another poly-size quantum circuit with gates of fan-in $\leq 2$ that tolerates random noise independently occurring on all wires at…

Quantum Physics · Physics 2007-05-23 Alexander A. Razborov

We investigate the boundary between classical and quantum computational power. This work consists of two parts. First we develop new classical simulation algorithms that are centered on sampling methods. Using these techniques we generate…

Quantum Physics · Physics 2012-02-20 M. Van den Nest

It has been known for almost 30 years that quantum circuits with interspersed depolarizing noise converge to the uniform distribution at $\omega(\log n)$ depth, where $n$ is the number of qubits, making them classically simulable. We show…

Quantum Physics · Physics 2025-10-09 Jon Nelson , Joel Rajakumar , Michael J. Gullans

Quantum magic is a necessary resource for quantum computers to be not efficiently simulable by classical computers. Previous results have linked the amount of quantum magic, characterized by the number of $T$ gates or stabilizer rank, to…

Quantum Physics · Physics 2025-02-07 Yifan Zhang , Yuxuan Zhang

The synthesis of quantum operators involves decomposing general quantum gates into the gate set supported by a given quantum device. Multi-controlled gates are essential components in this process. In this work, we present an improved…

Quantum Physics · Physics 2025-08-13 Jefferson D. S. Silva , Adenilton J. da Silva

We explore the feasibility of implementing a small surface code with 9 data qubits and 8 ancilla qubits, commonly referred to as surface-17, using a linear chain of 171Yb+ ions. Two-qubit gates can be performed between any two ions in the…

We propose a universal gate set for quantum computing with all-to-all connectivity and intrinsic robustness to bit-flip errors based on parity encoding. We show that logical controlled phase gate and $R_z$ rotations can be implemented in…

Quantum Physics · Physics 2022-11-03 Michael Fellner , Anette Messinger , Kilian Ender , Wolfgang Lechner

In order to demonstrate non-trivial quantum computations experimentally, such as the synthesis of arbitrary entangled states, it will be useful to understand how to decompose a desired quantum computation into the shortest possible sequence…

Quantum Physics · Physics 2009-11-10 Farrokh Vatan , Colin Williams