Measuring the Charge of a Single Dielectric Nanoparticle Using a High-QOptical Microresonator

Abstract

Measuring the charge of a nanoparticle is of great importance in many fields including optics, astronomy, biochemistry, atmospheric science, environmental engineering, and dusty plasma. Here, we propose to use a high-Q whispering-gallery-mode (WGM) optical microresonator to detect the surface and bulk charge of a dielectric nanoparticle. Because of the modification of nanoparticle conductivity induced by the surplus electrons, both the coupling strength between the nanoparticle and the WGM and the dissipation changes compared with the case of a neutral nanoparticle. The charge density can be inferred from the transmission spectrum of the WGM microresonator. By monitoring the mode splitting, the linewidth broadening or the resonance dip value of the transmission spectrum, surface (bulk) electron density as low as 0.007 nm −2 (0.001 nm −3) can be detected for nanoparticles with negative (positive) electron affinity. The high sensitivity is attributed to the ultranarrow resonance linewidth and small mode volume of the microresonator.

Graphene-Activated Optoplasmonic Nanomembrane Cavities for Photodegradation Detection

“…In addition, more sensitive degradation detection beyond organic dyes, such as gas molecules like NO 2 and CO 2 , is feasible as the Q-factor of the optoplasmonic sensor further improves. With investigations on the present sensing platform, the basic mechanisms underlying the degradation process, especially in the presence of a photocatalyst, may be discovered through analyzing the optical signals such as resonance shift, mode splitting, and linewidth broadening. ,, …”

“…With investigations on the present sensing platform, the basic mechanisms underlying the degradation process, especially in the presence of a photocatalyst, may be discovered through analyzing the optical signals such as resonance shift, mode splitting, and linewidth broadening. 6,12,66…”

Cooling a Rotating Mirror Coupled to a Single Laguerre–Gaussian Cavity Mode Using Parametric Interactions

“…In recent years, cavity optomechanical systems have become a popular research field in quantum optics, which focus on the interaction between a mechanical oscillator and light field via radiation pressure. This kind of interaction makes the optical degrees of freedom and mechanical degrees of freedom couple and let the cavity optomechanical system play a role in precision measurement and force sensors [ 1 , 2 , 3 ]. When the cavity optomechanical system is driven by a strong coupling field, it also becomes transparent to the input probing field due to the destructive interferences between the input probing field and the anti-Stokes fields generated by the interactions of the coupling field with the cavity, which is called optomechanically induced transparency (OMIT) [ 4 , 5 , 6 ].…”

Comparative study an effect of polymethyl methacrylate coating on optical microbottle resonator for enhancing sensing performance for ethanol liquid sensor

“…Due to low intrinsic losses and minimal assembly method, the research on OMR increased its popularity to be explored wider. 3,[15][16][17][18] The microbottle resonator (MBR) is a sub-class of OMR that captured huge intention recently. The technique is known as "soften-and-compress" used to form the MBR from the silica fiber SMF-28.…”

“…By concepts, WGMs spatially moved crossed the resonator axis, allowing high optical forces that helped to expand photon lifetime and increase the quality of the mode. Due to low intrinsic losses and minimal assembly method, the research on OMR increased its popularity to be explored wider 3,15–18 . The microbottle resonator (MBR) is a sub‐class of OMR that captured huge intention recently.…”