Measuring fluorescence to track a quantum emitter's state: a theory review

Lewalle, Philippe; Manikandan, Sreenath K.; Elouard, Cyril; Jordan, Andrew N.

doi:10.1080/00107514.2020.1747201

Cited by 19 publications

(37 citation statements)

References 72 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Phase-preserving amplification can be realized by employing parametric amplifiers, travelling wave parametric-amplifiers and Josephson parametric amplifiers [31,32,[66][67][68][69]. In phase-preserving amplification, the cavity field is mixed with a coherent local oscillator, which gives access to both quadratures of the field [8,10,13]. This mixing leads to two readout signals I and Q, which are proportional to the real and imaginary parts of a random field amplitude β, according to the probability distribution…”

Section: B Phase-preserving Amplificationmentioning

confidence: 99%

“…So far, we have analyzed the continuous monitoring of a qudit with phase-preserving measurements using a stochastic master equation. To compare with the dynamics due to backaction from phase-sensitive measurements, we will perform an equivalent calculation using Kraus operators [10]. As mentioned previously, making a phase-preserving measurement on the joint quditresonator state (4) gives the real and imaginary part of a field amplitude β.…”

Section: Comparison Of Phase-preserving and Phase-sensitive Measureme...mentioning

confidence: 99%

“…Instead of performing phase-preserving measurements, as we have been doing, one can also carry out phasesensitive measurements [78][79][80]. In the phase-sensitive case, one quadrature is amplified while the other is suppressed, which is equivalent to projecting along the eigenstate of one quadrature [10,13]. This gives one measurement result rather than two, as is typical in homodyne measurements.…”

Section: B Phase-sensitive Measurementmentioning

confidence: 99%

“…Continuous measurements have been used to track fluorescence from a quantum emitter [10], and explore multi-time correlators [25] and the arrow of time [26]. Quantum trajectories and continuous measurement have been discussed in the context of solid-state charge qubits [27].…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Continuous measurement of a qudit using dispersively coupled radiation

Steinmetz,

Das,

Siddiqi

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

We present an analysis of the continuous monitoring of a qudit coupled to a cavity using both phase-preserving and phase-sensitive amplification. We construct a stochastic master equation that describes the quantum trajectories of the system, and derive the corresponding Lindblad operators. We find that the measurement backaction causes spiralling in the state coordinates during collapse, which increases as the system levels become less distinguishable. We discuss two examples: a twolevel system, and an N-dimensional system and meter with rotational symmetry in the quadrature space. We also provide a comparison of the effects of phase-preserving and phase-sensitive detection on the master equation, and show that the average behaviour is the same in both cases, but individual trajectories collapse at different rates depending on the measurement axis in the quadrature plane.

show abstract

Section: B Phase-preserving Amplificationmentioning

confidence: 99%

Section: Comparison Of Phase-preserving and Phase-sensitive Measureme...mentioning

confidence: 99%

Section: B Phase-sensitive Measurementmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Continuous measurement of a qudit using dispersively coupled radiation

Steinmetz,

Das,

Siddiqi

et al. 2021

Preprint

Self Cite

View full text Add to dashboard Cite

show abstract

“…On the other, diffusive quantum trajectories have been analyzed via stochastic path integral methods, which have allowed "most-likely paths" (MLPs), following an optimal measurement record, to be computed [8][9][10]. These path integral methods, initially developed by Chantasri, Dressel, and Jordan (CDJ), have been applied to theory and experiment across several examples featuring continuouslymonitored qubits [8][9][10][11][12][13][14][15][16]. This formalism has not been applied to the continuously-monitored quantum harmonic oscillator or other continuous variable systems, however.…”

Section: Introductionmentioning

confidence: 99%

Stochastic Path Integral Analysis of the Continuously Monitored Quantum Harmonic Oscillator

Karmakar,

Lewalle,

Jordan

2021

Preprint

Self Cite

View full text Add to dashboard Cite

We consider the evolution of a quantum simple harmonic oscillator in a general Gaussian state under simultaneous time-continuous weak position and momentum measurements. We deduce the stochastic evolution equations for position and momentum expectation values and the covariance matrix elements from the system's characteristic function. By generalizing the Chantasri-Dressel-Jordan (CDJ) formalism (Chantasri et al. 2013 and to this continuous variable system, we construct its stochastic Hamiltonian and action. Action extremization gives us the equations for the most-likely readout paths and quantum trajectories. For steady states of the covariance matrix elements, the analytical solutions for these most-likely paths are obtained. Using the CDJ formalism we calculate final state probability densities exactly starting from any initial state. We also demonstrate the agreement between the optimal path solutions and the averages of simulated clustered stochastic trajectories. Our results provide insights into the time dependence of the mechanical energy of the system during the measurement process, motivating their importance for quantum measurement engine/refrigerator experiments.

show abstract

A pedagogical introduction to continuously monitored quantum systems and measurement-based feedback

Albarelli,

Genoni

2024

Physics Letters A

View full text Add to dashboard Cite

Measuring fluorescence to track a quantum emitter's state: a theory review

Cited by 19 publications

References 72 publications

Continuous measurement of a qudit using dispersively coupled radiation

Continuous measurement of a qudit using dispersively coupled radiation

Stochastic Path Integral Analysis of the Continuously Monitored Quantum Harmonic Oscillator

A pedagogical introduction to continuously monitored quantum systems and measurement-based feedback

Contact Info

Product

Resources

About