In this work, we have successfully engineered and examined suspended laterally vibrating resonators (LVRs) on a lithium niobate thin film on lithium niobate carrier wafer (LN-on-LN) platform, powered by aluminum interdigital transducers (IDTs). Unlike the lithium niobate-on-silicon system, the LN-on-LN platform delivers a stress-neutral lithium niobate thin film exhibiting the quality of bulk single crystal. The creation of these aluminum-IDTs-driven LN-on-LN resonators was achieved utilizing cutting-edge vapor-HF release techniques. Our testing revealed both symmetric (S0) and sheer horizontal (SH0) lateral vibrations in the LVR resonators. The resonators displayed a quality factor (Q) ranging between 500 and 2600, and coupling coefficient $k_{eff}^2$ up to 13.9%. The figure of merit (FOM) $k_{eff}^2 \times Q$ can reach as high as 294. The yield of these devices proved to be impressively reliable. Remarkably, our LN-on-LN devices demonstrated a consistently stable temperature coefficient of frequency (TCF) and good power handling. Given the low thermal conductivity of lithium niobate, our LN-on-LN technology presents promising potential for future applications such as highly sensitive uncooled sensors using monolithic chip integrated resonator arrays.
Electro-optic modulators with low voltage and large bandwidth are crucial for both analog and digital communications. Recently, thin-film lithium niobate modulators have enable dramatic performance improvements by reducing the required modulation voltage while maintaining high bandwidths. However, the reduced electrode gaps in such modulators leads to significantly higher microwave losses, which limit electro-optic performance at high frequencies. Here we overcome this limitation and achieve a record combination of low RF half-wave voltage of 1.3 V while maintaining electro-optic response with…
Segmented, or slow-wave electrodes have emerged as an index-matching solution to improve bandwidth of traveling-wave Mach Zehnder and phase modulators on the thin-film lithium niobate on insulator platform. However, these devices require the use of a quartz handle or substrate removal, adding cost and additional processing. In this work, a high-speed dual-output electro-optic intensity modulator in the thin-film silicon nitride and lithium niobate material system that uses segmented electrodes for RF and optical index matching is presented. The device uses a silicon handle and does not require…
With the usage of two transparent electrodes, organic solar cells are semitransparent and may be combined to parallel-connected multi-junction devices or used for innovative applications like power-generating windows. A challenging issue is the optimization of the electrodes, in order to combine high transparency with adequate electric properties. In the present work, we study the potential of sputter-deposited aluminum-doped zinc oxide (AZO) as an alternative to the widely used but relatively expensive indium tin oxide (ITO) as cathode material in semitransparent polymer-fullerene solar cells…
Bismuth based ternary oxide photocatalysts are of considerable interest in photoelectrochemical water splitting. Yet these oxides are highly stable in different environment, their relative inertness limits the available synthesis routes to obtain desired stoichiometry on the final product. This report describes a method to prepare barium bismuth niobate (specifically, Ba2(BiNb)O6 and Ba2Bi1.4Nb0.6 O6) target by sintering a mixture of individual oxides and successfully fabricate desired barium bismuth niobate thin film on TCO substrate. The surface morphology, physical, and chemical properties …
This article presents a bulk acoustic wave (BAW) resonator with complementary switchable operation in the first and second thickness extensional modes (TE1 and TE2) at 7.04 and 13.4 GHz. Two ferroelectric scandium aluminum nitride (Sc0.28Al0.72N) layers are alternatively stacked with three molybdenum electrodes, creating a laminated BAW resonator with independent switchability of polarization in constituent transducers. This enables intrinsic switchability of the resonator in TE1 and TE2 modes, when the ferroelectric Sc0.28Al0.72N layers are poled in the same or opposite directions, respective…
We report second harmonic generation from a titanium indiffused lithium niobate waveguide resonator device whose cavity length is locked to the fundamental pump laser using an on-chip phase modulator. The device remains locked for more than 5 minutes, producing more than 80\% of the initial second harmonic power. The stability of the system is seen to be limited by DC-drift, a known effect in many lithium niobate systems that include deposited electrodes. The presented device explores the suitability of waveguide resonators in this platform for use in larger integrated networks.
Electric field detection has been widely utilized in many fields such as scientific research and integrated circuits. To enhance the tuning sensitivity of E-field sensor, in this paper, we theoretically proposed a highly sensitive E-field sensor composed of etchless lithium niobate (LN) material and hybrid coupling-grating systems in the visible near-infrared regime. Such configuration supports high-quality factor quasi-BIC resonance, which generates strong localized field confinement. Due to the large electro-optic coefficient of LN material, one can shift the wavelength and reflection ratio …
Candidate overtone shear horizontal SAW resonators in thin-film lithium niobate for intermodal acousto-optic modulation
Wangzhijiang Innovation Center for Laser, Aerospace Laser Technology and System Department, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences（中国科学院上海光学精密机械研究所）；Center of Materials Science and Optoelectronics Engineering, University of Chinese Academy of Sciences（中国科学院大学物质科学与光电技术研究院）；School of Information Science and Technology, ShanghaiTech University（上海科技大学信息科学与技术学院）
We have demonstrated a fiber lithium ion battery (LIB) fabricated by co-twisting a LiFePO4 composite-coated copper wire (cathode) together with an aluminum wire (anode). An all-solid LiPF6 composite layer functioning both as the electrolyte and battery separator is deposited onto the two electrode wires before twisting. To characterize the electrochemical properties of the battery, charge-discharge tests with different C-rates are performed. The fiber LIB has an open-circuit voltage of ~3.4 V, and the typical specific capacity is found to be ~87 mAhg-1 at 0.5 C charge-discharge rate. Besides, …
The Organic Permeable Base Transistor (OPBT) is currently the fastest organic transistor with a transition frequency of 40 MHz. It relies on a thin aluminum base electrode to control the transistor current. This electrode is surrounded by a native oxide layer for passivation, currently created by oxidation in air. However, this process is not reliable and leads to large performance variations between samples, slow production and relatively high leakage currents. Here, we demonstrate for the first time that electrochemical anodization can be conveniently employed for the fabrication of high per…
Mechanical resonators made with monolithic piezoelectric quartz crystals are promising for studying new physical phenomena. High mechanical quality factors ($Q$) exhibited by the mm-sized quartz resonators make them ideal for studying weak couplings or long timescales in the quantum regime. However, energy losses through mechanical supports pose a serious limiting factor for obtaining high quality factors. Here we investigate how the $Q$ of quartz resonators at deep cryogenic temperatures can be limited by several types of losses related to anchoring. We first introduce means to reduce the mec…
