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Current quantum devices face challenges when dealing with large circuits due to error rates as circuit size and the number of qubits increase. The circuit wire-cutting technique addresses this issue by breaking down a large circuit into…

In realistic metrology, entangled probes are more sensitive to noise, especially for a correlated environment. The precision of parameter estimation with entangled probes is even lower than that of the unentangled ones in a correlated…

Quantum Physics · Physics 2021-12-22 Wan-Ting He , Huan-Yu Guang , Zi-Yun Li , Ru-Qiong Deng , Na-Na Zhang , Jie-Xing Zhao , Fu-Guo Deng , Qing Ai

We introduce a quantum control protocol that produces smooth, experimentally implementable control sequences optimized to combat temporally correlated noise for single qubit systems. The control ansatz is specifically chosen to be a…

Quantum Physics · Physics 2023-01-30 Yasuo Oda , Dennis Lucarelli , Kevin Schultz , B. David Clader , Gregory Quiroz

Due to the unreliability and limited capacity of existing quantum computer prototypes, quantum circuit simulation continues to be a vital tool for validating next generation quantum computers and for studying variational quantum algorithms,…

Quantum Physics · Physics 2021-04-01 Yipeng Huang , Steven Holtzen , Todd Millstein , Guy Van den Broeck , Margaret Martonosi

Resource consumption is an important issue in quantum information processing, particularly during the present NISQ era. In this paper, we investigate resource optimization of implementing multiple controlled operations, which are…

Quantum Physics · Physics 2024-02-08 Junhong Nie , Wei Zi , Xiaoming Sun

Noisy unsharp measurements incorporated in quantum information protocols may hinder performance, reducing the quantum advantage. However, we show that, unlike projective measurements which completely destroy quantum correlations between…

Quantum Physics · Physics 2025-07-01 Sudipta Mondal , Pritam Halder , Amit Kumar Pal , Aditi Sen De

Many qubit implementations are afflicted by correlated noise not captured by standard theoretical tools that are based on Markov approximations. While independent gate operations are a key concept for quantum computing, it is actually not…

Quantum Physics · Physics 2021-10-26 Pascal Cerfontaine , Tobias Hangleiter , Hendrik Bluhm

The resources required to characterise the dynamics of engineered quantum systems-such as quantum computers and quantum sensors-grow exponentially with system size. Here we adapt techniques from compressive sensing to exponentially reduce…

Quantum Physics · Physics 2011-04-19 A. Shabani , R. L. Kosut , M. Mohseni , H. Rabitz , M. A. Broome , M. P. Almeida , A. Fedrizzi , A. G. White

The characterization of a quantum device is a crucial step in the development of quantum experiments. This is accomplished via Quantum Process Tomography, which combines the outcomes of different projective measurements to deliver a…

Quantum Physics · Physics 2025-06-26 Francesco Di Colandrea , Nazanin Dehghan , Alessio D'Errico , Ebrahim Karimi

Many quantum algorithms rely on the measurement of complex quantum amplitudes. Standard approaches to obtain the phase information, such as the Hadamard test, give rise to large overheads due to the need for global controlled-unitary…

Quantum Physics · Physics 2024-05-29 Yilun Yang , Arthur Christianen , Mari Carmen Bañuls , Dominik S. Wild , J. Ignacio Cirac

In quantum computing, characterizing the full noise profile of qubits can aid in increasing coherence times and fidelities by developing error-mitigating techniques specific to the noise present. This characterization also supports efforts…

Modeling the dynamics of a quantum system connected to the environment is critical for advancing our understanding of complex quantum processes, as most quantum processes in nature are affected by an environment. Modeling a macroscopic…

We demonstrate mid-circuit measurements in a neutral atom array by shelving data qubits in protected hyperfine-Zeeman sub-states while non-destructively measuring an ancilla qubit. Measurement fidelity was enhanced using microwave repumping…

Quantum Physics · Physics 2024-05-31 T. M. Graham , L. Phuttitarn , R. Chinnarasu , Y. Song , C. Poole , K. Jooya , J. Scott , A. Scott , P. Eichler , M. Saffman

For an initially well designed but imperfect quantum information system, the process matrix is almost sparse in an appropriate basis. Existing theory and associated computational methods (L1-norm minimization) for reconstructing sparse…

Quantum Physics · Physics 2009-03-06 Robert L. Kosut

The presence of noise in quantum computers hinders their effective operation. Even though quantum error correction can theoretically remedy this problem, its practical realization is still a challenge. Testing and benchmarking noisy,…

Quantum Physics · Physics 2023-02-15 Adrian Ortega , Orsolya Kálmán , Tamás Kiss

Characterizing the nonclassicality of quantum systems under minimal assumptions is an important challenge for quantum foundations and technology. Here we introduce a theory-independent method of process tomography and perform it on a…

Quantum Physics · Physics 2026-03-18 Albert Aloy , Matteo Fadel , Thomas D. Galley , Caroline L. Jones , Markus P. Mueller

Computer simulation of observable phenomena is an indispensable tool for engineering new technology, understanding the natural world, and studying human society. Yet the most interesting systems are often complex, such that simulating their…

Quantum Physics · Physics 2017-08-23 Matthew S. Palsson , Mile Gu , Joseph Ho , Howard M. Wiseman , G. J. Pryde

We describe and demonstrate a method for the computation of quantum dynamics on small, noisy universal quantum computers. This method relies on the idea of `restarting' the dynamics; at least one approximate time step is taken on the…

Quantum Physics · Physics 2019-10-15 Matthew Otten , Cristian L. Cortes , Stephen K. Gray

Designing quantum processors is a complex task that demands advanced verification methods to ensure their correct functionality. However, traditional methods of comprehensively verifying quantum devices, such as quantum process tomography,…

Quantum Physics · Physics 2025-08-04 Keren Li , Peng Yan , Hanru Jiang , Nengkun Yu

The accumulation of quantum phase in response to a signal is the central mechanism of quantum sensing, as such, loss of phase information presents a fundamental limitation. For this reason approaches to extend quantum coherence in the…