Resonance-enhanced spectral funneling in Fabry–Perot resonators with a temporal boundary mirror

Abstract A temporal boundary refers to a specific time at which the properties of an optical medium are abruptly changed. When light interacts with the temporal boundary, its spectral content can be redistributed due to the breaking of continuous time-translational symmetry of the medium where light resides. In this work, we use this principle to demonstrate, at terahertz (THz) frequencies, the resonance-enhanced spectral funneling of light coupled to a Fabry–Perot resonator with a temporal boundary mirror. To produce a temporal boundary effect, we abruptly increase the reflectance of a mirror constituting the Fabry–Perot resonator and, correspondingly, its quality factor in a step-like manner. The abrupt increase in the mirror reflectance leads to a trimming of the coupled THz pulse that causes the pulse to broaden in the spectral domain. Through this dynamic resonant process, the spectral contents of the input THz pulse are redistributed into the modal frequencies of the high-Q Fabry–Perot resonator formed after the temporal boundary. An energy conversion efficiency of up to 33% was recorded for funneling into the fundamental mode with a Fabry–Perot resonator exhibiting a sudden Q-factor change from 4.8 to 48. We anticipate that the proposed resonance-enhanced spectral funneling technique could be further utilized in the development of efficient mechanically tunable narrowband terahertz sources for diverse applications.

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Boundary effect in competition processes

Journal of Applied Probability ◽

10.1017/jpr.2019.46 ◽

2019 ◽

Vol 56 (3) ◽

pp. 750-768

Author(s):

Vadim Shcherbakov ◽

Stanislav Volkov

Keyword(s):

Markov Chain ◽

Continuous Time ◽

Boundary Effect ◽

Competitive Interaction ◽

Continuous Time Markov Chain ◽

Urn Models ◽

Birth Processes ◽

Special Case

AbstractThis paper is devoted to studying the long-term behaviour of a continuous-time Markov chain that can be interpreted as a pair of linear birth processes which evolve with a competitive interaction; as a special case, they include the famous Lotka–Volterra interaction. Another example of our process is related to urn models with ball removal. We show that, with probability one, the process eventually escapes to infinity by sticking to the boundary in a rather unusual way.

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Direct Comb Vernier Spectroscopy for Fractional Isotopic Ratio Determinations

Sensors ◽

10.3390/s21175883 ◽

2021 ◽

Vol 21 (17) ◽

pp. 5883

Author(s):

Mario Siciliani de Cumis ◽

Roberto Eramo ◽

Jie Jiang ◽

Martin E. Fermann ◽

Pablo Cancio Pastor

Keyword(s):

Frequency Comb ◽

Isotopic Ratio ◽

Global Climate ◽

Composition Analysis ◽

Spectroscopic Techniques ◽

Spectral Content ◽

Co2 Gas ◽

Greenhouse Gasses ◽

Fitting Procedure ◽

Fabry Perot

Accurate isotopic composition analysis of the greenhouse-gasses emitted in the atmosphere is an important step to mitigate global climate warnings. Optical frequency comb–based spectroscopic techniques have shown ideal performance to accomplish the simultaneous monitoring of the different isotope substituted species of such gases. The capabilities of one such technique, namely, direct comb Vernier spectroscopy, to determine the fractional isotopic ratio composition are discussed. This technique combines interferometric filtering of the comb source in a Fabry–Perot that contains the sample gas, with a high resolution dispersion spectrometer to resolve the spectral content of each interacting frequency inside of the Fabry–Perot. Following this methodology, simultaneous spectra of ro-vibrational transitions of 12C16O2 and 13C16O2 molecules are recorded and analyzed with an accurate fitting procedure. Fractional isotopic ratio 13C/12C at 3% of precision is measured for a sample of CO2 gas, showing the potentialities of the technique for all isotopic-related applications of this important pollutant.

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The size order of the state vector of a continuous-time homogeneous Markov system with fixed size

Journal of Applied Probability ◽

10.1239/jap/1005091028 ◽

2001 ◽

Vol 38 (3) ◽

pp. 635-646

Author(s):

I. Kipouridis ◽

G. Tsaklidis

Keyword(s):

Lower Bound ◽

Convergence Rate ◽

Continuous Time ◽

State Vector ◽

The State ◽

Specific Time ◽

Fixed Size ◽

Geometric Characteristics ◽

Markov System ◽

Selection Of

The variation of the state vectors p(t) = (pi(t)) of a continuous-time homogeneous Markov system with fixed size is examined. A specific time t0 after which the size order of the elements pi(t) becomes stable provides a criterion of the system's convergence rate. A method is developed to find t0 and a quickly evaluated lower bound for t0. This method is based on the geometric characteristics and the volumes of the attainable structures. Moreover, a condition concerning the selection of starting vectors p(0) is given so that the vector functions p(t) retain the same size order for every time greater than a given time t.

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The size order of the state vector of a continuous-time homogeneous Markov system with fixed size

Journal of Applied Probability ◽

10.1017/s0021900200018805 ◽

2001 ◽

Vol 38 (03) ◽

pp. 635-646

Author(s):

I. Kipouridis ◽

G. Tsaklidis

Keyword(s):

Lower Bound ◽

Convergence Rate ◽

Continuous Time ◽

State Vector ◽

The State ◽

Specific Time ◽

Fixed Size ◽

Geometric Characteristics ◽

Markov System ◽

Selection Of

The variation of the state vectors p (t) = (p i (t)) of a continuous-time homogeneous Markov system with fixed size is examined. A specific time t 0 after which the size order of the elements p i (t) becomes stable provides a criterion of the system's convergence rate. A method is developed to find t 0 and a quickly evaluated lower bound for t 0. This method is based on the geometric characteristics and the volumes of the attainable structures. Moreover, a condition concerning the selection of starting vectors p (0) is given so that the vector functions p (t) retain the same size order for every time greater than a given time t.

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Investigation of the spectral content of a cw CO laser output using a high-resolution scanning Fabry-Perot interferometer

Optics & Laser Technology ◽

10.1016/0030-3992(76)90006-2 ◽

1976 ◽

Vol 8 (5) ◽

pp. 221-226 ◽

Cited By ~ 7

Author(s):

R.B. Dennis ◽

H.A. Mackenzie ◽

G. McClelland ◽

F.H. Hamza

Keyword(s):

High Resolution ◽

Laser Output ◽

Spectral Content ◽

Co Laser ◽

Fabry Perot

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Heavy Tails of Discounted Aggregate Claims in the Continuous-Time Renewal Model

Journal of Applied Probability ◽

10.1017/s0021900200002965 ◽

2007 ◽

Vol 44 (02) ◽

pp. 285-294 ◽

Cited By ~ 2

Author(s):

Qihe Tang

Keyword(s):

Asymptotic Formula ◽

Continuous Time ◽

Heavy Tails ◽

Tail Behavior ◽

Renewal Model ◽

Discounted Aggregate Claims ◽

Aggregate Claims ◽

Tail Asymptotic

We study the tail behavior of discounted aggregate claims in a continuous-time renewal model. For the case of Pareto-type claims, we establish a tail asymptotic formula, which holds uniformly in time.

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Hearing in Mice by GSR Audiometry: II. Magnitude of Unconditioned GSR as a Function of Intensity and Frequency Interactions

Journal of Speech and Hearing Research ◽

10.1044/jshr.1101.169 ◽

1968 ◽

Vol 11 (1) ◽

pp. 169-178 ◽

Cited By ~ 4

Author(s):

Alan Gill ◽

Charles I. Berlin

Keyword(s):

Power Law ◽

Response Magnitude ◽

Single Units ◽

Spectral Content ◽

Hearing Sensitivity ◽

Subjective Magnitude ◽

Orderly Fashion ◽

Viiith Nerve

The unconditioned GSR’s elicited by tones of 60, 70, 80, and 90 dB SPL were largest in the mouse in the ranges around 10,000 Hz. The growth of response magnitude with intensity followed a power law (10 .17 to 10 .22 , depending upon frequency) and suggested that the unconditioned GSR magnitude assessed overall subjective magnitude of tones to the mouse in an orderly fashion. It is suggested that hearing sensitivity as assessed by these means may be closely related to the spectral content of the mouse’s vocalization as well as to the number of critically sensitive single units in the mouse’s VIIIth nerve.

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