English
Related papers

Related papers: Improved Quantum Sensing by Spectral Design

200 papers

We show that a polynomial H(N) of degree N of a harmonic oscillator hamiltonian allows us to devise a fully solvable continuous quantum system for which the first N discrete energy eigenvalues can be chosen at will. In general such a choice…

Quantum Physics · Physics 2021-02-02 Ole Steuernagel , Andrei Klimov

We test the bootstrap approach for determining the spectrum of one dimensional Hamiltonians, following the recent approach of Han, Hartnoll, and Kruthoff. We focus on comparing the bootstrap method data to known analytical predictions for…

High Energy Physics - Theory · Physics 2021-09-17 David Berenstein , George Hulsey

We consider a free quantum particle in one dimension whose mass profile exhibits jump discontinuities. The corresponding Hamiltonian is a self-adjoint realisation of the kinetic-energy operator, with the specific realisation determined by…

Mathematical Physics · Physics 2026-04-27 Fabio Deelan Cunden , Giovanni Gramegna , Marilena Ligabò

The ability to use quantum technology to achieve useful tasks, be they scientific or industry related, boils down to precise quantum control. In general it is difficult to assess a proposed solution due to the difficulties in characterising…

Quantum Physics · Physics 2020-12-07 Akram Youssry , Gerardo A. Paz-Silva , Christopher Ferrie

The engineering and control of devices at the quantum-mechanical level--such as those consisting of small numbers of atoms and photons--is a delicate business. The fundamental uncertainty that is inherently present at this scale manifests…

Probability · Mathematics 2009-05-02 Luc Bouten , Ramon van Handel , Matthew R. James

Quantum machine learning methods often rely on fixed, hand-crafted quantum encodings that may not capture optimal features for downstream tasks. In this work, we study the power of quantum autoencoders in learning data-driven quantum…

In this paper, we study the control of a class of time-invariant linear ensemble systems whose natural dynamics are linear in the system parameter. This class of ensemble control systems arises from practical engineering and physical…

Optimization and Control · Mathematics 2014-10-07 Jr-Shin Li , Ji Qi

Optimal quantum control of continuous variable systems poses a formidable computational challenge because of the high-dimensional character of the system dynamics. The framework of quantum invariants can significantly reduce the complexity…

Eigenvalue-based detectors are considered as an important method of spectrum sensing since they do not require the information about the primary user (PU) signal. In this paper we propose a method to improve the performance of the…

Information Theory · Computer Science 2015-04-30 Liping Du , Mihir Laghate , Chun-Hao Liu , Danijela Cabric

We present a unitary control pulse design method for a scalable quantum computer architecture based on electron spins in lateral quantum dots. We employ simultaneous control of spin interactions and derive the functional forms of spin…

Quantum Physics · Physics 2024-02-14 Bohdan Khromets , Zach D. Merino , Jonathan Baugh

Optimal control techniques provide a means to tailor the control pulses required to generate customized quantum gates, which helps to improve the resilience of quantum simulations to gate errors and device noise. However, the significant…

We consider the problem of parameter estimation from a generalized linear model with a random design matrix that is orthogonally invariant in law. Such a model allows the design have an arbitrary distribution of singular values and only…

Statistics Theory · Mathematics 2026-02-11 Yihan Zhang , Hong Chang Ji , Ramji Venkataramanan , Marco Mondelli

Optimal control theory is an effective tool to improve parameter estimation of quantum systems. Different methods can be employed for the design of the control protocol. They can be based either on Quantum Fischer Information (QFI)…

Quantum Physics · Physics 2023-06-21 Quentin Ansel , Etienne Dionis , Dominique Sugny

It is known that the unified transform method may be used to solve any well-posed initial-boundary value problem for a linear constant-coefficient evolution equation on the finite interval or the half-line. In contrast, classical methods…

Spectral Theory · Mathematics 2014-08-19 David A. Smith

Measurement in quantum simulations provides a means for extracting meaningful information from a complex quantum state, and for quantum computing reducing the complexity of measurement will be vital for near-term applications. For most…

Quantum Physics · Physics 2021-05-11 Scott E. Smart , David A. Mazziotti

Along with the scaling of dimensions in quantum systems, transitions between the system's energy levels would become close in frequency, which are conventionally resolved by weak and lengthy pulses. Here, we extend and experimentally…

A quantum emitter in a dynamic environment may have its energy levels drift uncontrollably in time with the fluctuating bath. This can result in an emission/absorption spectrum that is spread over a broad range of frequencies and presents a…

Quantum Physics · Physics 2023-03-08 Herbert F Fotso

Quantum simulation is a promising near term application for mesoscale quantum information processors, with the potential to solve computationally intractable problems at the scale of just a few dozen interacting quantum systems. Recent…

Quantum Physics · Physics 2014-08-14 David L. Hayes , Steven T. Flammia , Michael J. Biercuk

We investigate the role of quantum monitoring in the dynamical manifestations of Hamiltonian quantum chaos. Specifically, we analyze the generalized spectral form factor, defined as the survival probability of a coherent Gibbs state under…

Quantum Physics · Physics 2026-02-04 Preethi Gopalakrishnan , András Grabarits , Adolfo del Campo

We develop and demonstrate a technique to engineer universal unitary baths in quantum systems. Using the correspondence between unitary decoherence due to ambient environmental noise and errors in a control system for quantum bits, we show…

Quantum Physics · Physics 2015-06-19 A. Soare , H. Ball , D. Hayes , X. Zhen , M. C. Jarratt , J. Sastrawan , H. Uys , M. J. Biercuk