&lt;title&gt;New developments of resonant acousto-optics in semiconductors&lt;/title&gt;

Sapriel, J.; Renosi, P.; Berre, P. Le

doi:10.1117/12.222752

Cited by 8 publications

(7 citation statements)

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“…The RamanNath approach for the diffraction of light from ultrasonic waves also has the benefit of providing an absolute measurement of the pressure amplitude (Klein 1976, Sapriel 1976, Gottlieb 1986. It has been shown (Nagai 1986) that the Raman-Nath method even for small curvature of the phase fronts leads to large errors.…”

Section: Introductionmentioning

confidence: 99%

The Tensile Strength of Liquid Helium Four

Nissen¹

2000

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It is well known that most liquids exhibit a tensile strength which is much smaller in magnitude than the tensile strength predicted by homogeneous nucleation theory. This lack of agreement is usually attributed to the difficulty of preparing liquid samples free from foreign gases which act as heterogeneous nucleation sites.Liq"lid heliurr. occupies a unique place among liquids for tensile strength measurements because all fcreign gases are frozen OLt at liquid helium temperatures. LIST OF FIGURESAt Equilibrium, a van der Waals substance Exhibits a Phase Change . . . . . 2.A Schematic Representation of the Work If instead of expanding the stable liquid slowly at equilibrium, the volume is suddenly increased, the liquid will penetrate into the metastable region along the curve BC. The metastable state is a state in which the Gibbs free energy is at a local rather than a global minimum.After a characteristic mean time, , which is highly dependent on the depth of penetration into the metastable region, the liquid will decompose to a stable equilibrium configuration on the coexistence curve. When T/T c is less than about 0.8, rapid stretching of the liquid into the metastable region can result in negative pressure such as point G in Fig. 1. Point C lies on the liquid spinodal, the curve marking the transition to instability, and represents a true limit to the tensile strength of the liquid. In practice this limit is not reached, rather the tensile strength is determined by kinetic rates of bubble formation in the metastable region. THE WORK REQUIRED TO FORM A BUBBLEThe rate of bubble formation is calculated by considering the minimum work that must be done to form a vapor bubble in the liquid. An amount of work equal to the surface tension times the surface area, aA, must be done to form a cavity. Part of the work is done by the gas vaporized into the cavity so that the total work (W) needed to ·form a bubble iswhere PG is the pressure of the gas in the bubble, PL is the pressure of the surrounding liquid, VG is the volume of the bubble, x is the number of molecules vaporized into the cavity, ~G and ~L are the chemical potentials of the gas and vapor respectively. On the coexistence curve, the pressure of the gas and the pressure of the liquid are equal to the vapor pressure. The chemical potentials are also equal on the coexistence curve, so that the work necessary to form a bubble rises to infinity as the bubble radius is increased (curve a of Fig.2). If the liquid is brought rapidly into the metastable region by means of a pressure excursion .then the following conditions will hold: PL < P G and ~ G < ~ L. Under these conditions, the work necessary to form a bubble increases to a maximum w P-P-=05 -12 r Figure 2. A schematic representatioc of tte work n~eded to form a critical size bubble as a function of bubble radius. On the sa.turated vapor pressure curve, the work ris~s monotonically (curve a). As the liquid is brought into the metastable regio~, the work necessary to form a bubble of radius r first in...

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Section: Introductionmentioning

confidence: 99%

The Tensile Strength of Liquid Helium Four

Nissen¹

2000

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“…The approximation is valid for the length of propagation It should be noted that in practice, such dimensions may not be convenient for optical adjustment. However, for dimensions of about h = 1 mm, taking into account the attenuation value of 20db/cm at 1 GHz [22], [23], it can be argued that our device can operate at 1 GHz without significant acoustic losses.…”

Section: Discussionmentioning

confidence: 99%

Efficient Acousto-Optical Light Modulation at the Mid-Infrared Spectral Range by Planar Semiconductor Structures Supporting Guided Modes

et al. 2020

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Acousto-optical devices, such as modulators, filters or deflectors, implement a simple and effective way of light modulation and signal processing techniques. However, their operation wavelengths are restricted to visible and near-infrared frequency region due to a quadratic decrease of the efficiency of acousto-optical interaction with the wavelength increase. At the same time, almost all materials with high value of acousto-optic figure of merit are non-transparent at wavelengths larger than 5 µm, while the transparent materials possess significantly lower acousto-optic figure of merit. Here we propose and demonstrate by calculations how these limitations could be overcome using specially designed planar semiconductor structures supporting electromagnetic modes strongly coupled to the incident light in the Otto configuration. Such approach could be used for a novel efficient acousto-optical device operating in middle infrared range of 8-14 µm. Acoustic wave excited by a piezoelectric transducer in a semi-conductor prism is utilized to modulate the coupling coefficient of the incident light to the semiconductor structure which results in up to 100% modulation of the transmitted light at the spatial scale less than the ultrasound wavelength. It allows to utilize acoustic waves with short decay distance and therefore, it provides a unique possibility to achieve an efficient acousto-optical modulation at frequencies over several gigahertz, which are unreachable for traditional acousto-optics.

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“…Therefore, a 1/4 wave plate connected to a mechanical motor with rotating frequency ω within the kHz range, which is much lower than the laser frequency of several hundreds of THz, effectively provides a time-modulated Rabi coupling J Ω (t) = J 0 Ω cos(ωt + δ). We can use, for instance, an acousto-optic modulator (AOM) to change both the amplitude and the polarization of the pump laser 26,27 . In the following discussion, we suppose that all the physical observables are stroboscopically measured at integer of time periods, which has already been realized and well controlled in experiments 1 .…”

Section: Experimental Realization Of Time Periodically Driven Modelmentioning

confidence: 99%

Quantum phase diagram for two species hardcore bosons in one-dimensional optical lattices with the resonantly driven Rabi frequency

Zhong,

Wang,

et al. 2022

Preprint

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We propose an experimental realization of using time-periodically modulated Rabi oscillation and consider two species of hard-core bosons with density dependent hoppings in a one-dimensional optical lattice. Different from the previous work [Phys. Rev. Research 2, 013275 (2020)], in the first resonance region, the intra-species hopping in the effective Hamiltonian occurs only if the density discrepancy of the other species on these sites is zero, while the inter-species hopping process is allowed once the relevant density discrepancy becomes nonzero. The quantum phase diagram for integer-1 filling is determined by combining analytic calculations and various numerical methods. We find that in the limit of dominant J1, the system becomes a double-degenerate dimerized state, with breaking translation symmetry spontaneously. Interplay of J0, J1 and the fixed Ū = 1 leads to three BKT transition lines and a tricritical BKT point. Exact transition lines are obtained by extrapolation following the level spectroscopic technique. Besides, general physical properties, including the charge gap, neutral gap, superfluidity density and dimerization strength, are investigated as well.

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<title>New developments of resonant acousto-optics in semiconductors</title>

Cited by 8 publications

References 0 publications

The Tensile Strength of Liquid Helium Four

The Tensile Strength of Liquid Helium Four

Efficient Acousto-Optical Light Modulation at the Mid-Infrared Spectral Range by Planar Semiconductor Structures Supporting Guided Modes

Quantum phase diagram for two species hardcore bosons in one-dimensional optical lattices with the resonantly driven Rabi frequency

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