Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userSingle-photon blockade in doubly resonant nanocavities with second-order nonlinearity
331
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
We propose the use of nanostructured photonic nanocavities made of second-order nonlinear materials as prospective passive devices to generate strongly sub-Poissonian light via single-photon blockade of an input coherent field. The simplest scheme is based on the requirement that the nanocavity be doubly resonant, i.e. possess cavity modes with good spatial overlap at both the fundamental and second-harmonic frequencies. We discuss feasibility of this scheme with state-of-the art nanofabrication technology, and the possibility to use it as a passive single-photon source on-demand.
rate research
Read More
It is shown that non-centrosymmetric materials with bulk second-order nonlinear susceptibility can be used to generate strongly antibunched radiation at an arbitrary wavelength, solely determined by the resonant behavior of suitably engineered coupled microcavities. The proposed scheme exploits the unconventional photon blockade of a coherent driving field at the input of a coupled cavity system, where one of the two cavities is engineered to resonate at both fundamental and second harmonic frequencies, respectively. Remarkably, the unconventional blockade mechanism occurs with reasonably low quality factors at both harmonics, and does not require a sharp doubly-resonant condition for the second cavity, thus proving its feasibility with current semiconductor technology.
We performed quantum manipulations of the multi-level spin system S=5/2 of a Mn$^{2+}$ ion, by means of a two-tone pulse drive. The detuning between the excitation and readout radio frequency pulses allows one to select the number of photons involved in a Rabi oscillation as well as increase the frequency of this nutation. Thus detuning can lead to a resonant multi-photon process. Our analytical model for a two-photon process as well as a numerical generalization fit well the experimental findings, with implications in the use of multi-level spin systems as tunable solid state qubits.
Resonant Raman spectra of single layer WS$_{2}$ flakes are presented. A second order Raman peak (2LA) appears under resonant excitation with a separation from the E$^{1}_{2g}$ mode of only $4$cm$^{-1}$. Depending on the intensity ratio and the respective line widths of these two peaks, any analysis which neglects the presence of the 2LA mode can lead to an inaccurate estimation of the position of the E$^{1}_{2g}$ mode, leading to a potentially incorrect assignment for the number of layers. Our results show that the intensity of the 2LA mode strongly depends on the angle between the linear polarization of the excitation and detection, a parameter which is neglected in many Raman studies.
Optical nonlinearity plays a pivotal role in quantum information processing using photons, from heralded single-photon sources to long-sought quantum repeaters. Despite the availability of strong light-atom interaction, an all-optical nonlinearity is highly desired for more scalable quantum protocols. Here, we realize quantum nanophotonic integrated circuits in thin-film InGaP with a record-high second-order optical nonlinearity of $1.5%$---the ratio of the single-photon trimodal coupling strength ($g/2pi=11.2$ MHz) and cavity-photon loss rate. We demonstrate photon-pair generation via degenerate spontaneous parametric down conversion in the InGaP photonic circuit with an ultrahigh rate exceeding 27.5 MHz per 1 $mu$W pump power and large coincidence-to-accidental ratio up to $1.4times 10^4$. Our work shows InGaP as a potentially transcending platform for quantum nonlinear optics and quantum information applications.
Second order optical nonlinear processes involve the coherent mixing of two electromagnetic waves to generate a new optical frequency, which plays a central role in a variety of applications, such as ultrafast laser systems, rectifiers, modulators, and optical imaging. However, progress is limited in the mid-infrared (MIR) region due to the lack of suitable nonlinear materials. It is desirable to develop a robust system with a strong, electrically tunable second order optical nonlinearity. Here we demonstrate theoretically that AB-stacked bilayer graphene (BLG) can exhibit a giant and tunable second order nonlinear susceptibility chi ^(2) once an in-plane electric field is applied. chi^(2) can be electrically tuned from 0 to ~ {10^5 pm/V}, three orders of magnitude larger than the widely used nonlinear crystal AgGaSe2. We show that the unusually large chi^(2) arises from two different quantum enhanced two-photon processes thanks to the unique electronic spectrum of BLG. The tunable electronic bandgap of BLG adds additional tunability on the resonance of chi^(2), which corresponds to a tunable wavelength ranging from ~2.6 {mu}m to ~3.1 {mu}m for the up-converted photon. Combined with the high electron mobility and optical transparency of the atomically thin BLG, our scheme suggests a new regime of nonlinear photonics based on BLG.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
