Lithium niobate photonic chip could realize diverse optical engineering for various applications benefiting from its excellent optical performances. In this letter, we demonstrate monolithic photonic chips for multi-channel sum-frequency conversion based on reverse-proton-exchange periodically poled lithium niobate waveguides, with the different channels showing uniform and excellent conversion efficiencies. To obtain a robust device and provide a convenient interface for applications, the integrated chip is fiber coupled with two fiber arrays. The packaged chip then forms the core of a multi-channel up conversion single photon detector. In each channel the input signal interacts with a 1950-nm single frequency pump laser and the sum frequency output is spectrally filtered and detected by a silicon avalanche photodiode. Average detection efficiency (DE) of 23.2 % and noise count rate (NCR) of 557 counts per second (cps) are achieved, with a standard deviation of 2.73 % and 48 cps over the 30 channels, as well as optical isolation (OI) between nearby channels of more than 71 dB, which are excellent for the extensive applications of monolithic photonic chips in fields including deep space laser communication, high-rate quantum key distribution and single-photon imaging.
Photonic quantum technologies such as quantum cryptography, photonic quantum metrology, photonic quantum simulators and computers will largely benefit from highly scalable and small footprint quantum photonic circuits. To perform fully on-chip quantum photonic operations, three basic building blocks are required: single-photon sources, photonic circuits and single-photon detectors. Highly integrated quantum photonic chips on silicon and related platforms have been demonstrated incorporating only one or two of these basic building blocks. Previous implementations of all three components were ma…
Metal-halide perovskites are promising lasing materials for realization of monolithically integrated laser sources, the key components of silicon photonic integrated circuits (PICs). Perovskites can be deposited from solution and require only low temperature processing leading to significant cost reduction and enabling new PIC architectures compared to state-of-the-art lasers realized through costly and inefficient hybrid integration of III-V semiconductors. Until now however, due to the chemical sensitivity of perovskites, no microfabrication process based on optical lithography and therefore…
Advances in microresonator-based soliton generation promise chip-scale integration of optical frequency comb for applications spanning from time keeping to frequency synthesis. Miniaturized cavities harness Kerr nonlinearity and enable terahertz soliton repetition rates. However, such high repetition rates are not amenable to direct electronic detection. Here, we demonstrate hybrid Kerr and electro-optic microcombs using the lithium niobate thin film that exhibits both Kerr and Pockels nonlinearities. By interleaving the high-repetition-rate Kerr soliton comb with the low-repetition-rate elect…
Microfluidic mixing is a fundamental functionality in most lab on a chip (LOC) systems,whereas realization of efficient mixing is challenging in microfluidic channels due to the small Reynolds numbers. Here, we design and fabricate a compact three-dimensional (3D) micromixer to enable efficient mixing at various flow rates. The performance of the fabricated micromixer was examined using blue and red inks. The extreme flexibility in fabricating microfluidic structures of arbitrary 3D geometries using femtosecond laser micromachining allows us to tackle the major disadvantageous effects for opti…
Integrated optical isolators have been a longstanding challenge for photonic integrated circuits (PIC). An ideal integrated optical isolator for PIC should be made by a monolithic process, have a small footprint, exhibit broadband and polarization-diverse operation, and be compatible with multiple materials platforms. Despite significant progress, the optical isolators reported so far do not meet all these requirements. In this article we present monolithically integrated broadband magneto-optical isolators on silicon and silicon nitride (SiN) platforms operating for both TE and TM modes with …
High-speed laser frequency actuation is critical in all applications employing lasers and frequency combs, and is prerequisite for phase locking, frequency stabilization and stability transfer among multiple optical carriers. Soliton microcombs have emerged as chip-scale, broadband and low-power-consumption frequency comb sources.Yet, integrated microcombs relying on thermal heaters for on-chip actuation all exhibit only kilohertz actuation bandwidth. Consequently, high-speed actuation and locking of microcombs have been attained only with off-chip bulk modulators. Here, we present high-speed …
Microresonator Kerr frequency combs, which rely on third-order nonlinearity ($χ^{(3)}$), are of great interest for a wide range of applications including optical clocks, pulse shaping, spectroscopy, telecommunications, light detection and ranging (LiDAR) and quantum information processing. Many of these applications require further spectral and temporal control of the generated frequency comb signal, which is typically accomplished using additional photonic elements with strong second-order nonlinearity ($χ^{(2)}$). To date these functionalities have largely been implemented as discrete off-ch…
We overcome the difficulty in realizing a monolithic waveguide-coupled microring laser integrated on erbium-doped thin film lithium niobate (Er: TFLN) using photolithography assisted chemo-mechanical etching (PLACE) technique. We demonstrate an integrated single-frequency microring laser operating around 1531 nm wavelength. The PLACE technique, enabling integrated Er: TFLN photonics with low propagation loss, can thus be used to realize low cost mass production of monolithic on-chip microlasers with applications ranging from optical communication and photonic integrated circuit (PIC) to precis…
Silicon photonic integration has gained great success in many application fields owing to the excellent optical device properties and complementary metal-oxide semiconductor (CMOS) compatibility. Realizing monolithic integration of III-V lasers and silicon photonic components on single silicon wafer is recognized as a long-standing obstacle for ultra-dense photonic integration, which can provide considerable economical, energy efficient and foundry-scalable on-chip light sources, that has not been reported yet. Here, we demonstrate embedded InAs/GaAs quantum dot (QD) lasers directly grown on t…
Semiconductor quantum dots in photonic integrated circuits enable scaling quantum-information processing to many single photons and quantum-optical gates. On-chip spectral filters are essential to achieve high-purity and coherent photon emission from quantum dots embedded in waveguides, without resorting to free-space optics. Such spectral filters should be tunable, to compensate for the inhomogeneous spectral distribution of the quantum dots transitions. Here, we report an on-chip filter monolithically integrated with quantum dots, that uses nanomechanical motion for tuning its resonant wavel…
We demonstrate a method to monolithically integrate nanowire-based quantum dot single photon sources on-chip using evanescent coupling. By deterministically placing an appropriately tapered III-V nanowire waveguide, containing a single quantum dot, on top of a silicon-based ridge waveguide, the quantum dot emission can be transferred to the ridge waveguide with calculated efficiencies close to 100%. As the evanescent coupling is bidirectional, the source can be optically pumped in both free-space and through the ridge waveguide. The latter onfiguration provides a self-contained, all-fiber, sin…
Electro-optic modulators provide a key function in optical transceivers and increasingly in photonic programmable Application Specific Integrated Circuits (ASICs) for machine learning and signal processing. However, both foundry ready silicon based modulators and conventional material based devices utilizing Lithium niobate fall short in simultaneously providing high chip packaging density and fast speed. Current driven ITO based modulators have the potential to achieve both enabled by efficient light matter interactions. Here, we introduce micrometer compact Mach Zehnder Interferometer (MZI) …
On-chip scalable integration represents a major challenge for practical quantum devices. One particular challenge is to implement on-chip optical readout of spins in diamond. This readout requires simultaneous application of optical and microwave fields along with an efficient collection of fluorescence. The readout is typically accomplished via bulk optics and macroscopic microwave transmission structures. We experimentally demonstrate an on-chip integrated structure for nitrogen vacancy (NV) spin-based applications, implemented in a single material layer with one patterning step. A nanodiamo…
Wavelength-dependent polarization state of light carries crucial information about light-matter interactions. However, its measurement is limited to bulky, energy-consuming devices, which prohibits many modern, portable applications. Here, we propose and demonstrate a chip-scale spectropolarimeter implemented using a CMOS-compatible silicon photonics technology. Four compact Vernier microresonator spectrometers are monolithically integrated with a broadband polarimeter consisting of a 2D nanophotonic antenna and a polarimetric circuit to achieve full-Stokes spectropolarimetric analysis. The pr…
Optical frequency combs enable all-solid-state spectrometers that will trigger a breakthrough in miniaturization and on-chip integration of mid-infrared sensing technology. Interband cascade lasers (ICLs) are an ideal candidate for practical implementations due to their low power consumption and zero-bias detection functionality. Here, we demonstrate the generation of self-starting ICL frequency combs. We show that the gain is fast enough to respond to beating of the intracavity field, which hinders the formation of short pulses. Instead, the ICL operates in a comb state, where the phases of t…
Hyperspectral imaging is a technique that allows for the creation of multi-color images. At terahertz wavelengths, it has emerged as a prominent tool for a number of applications, ranging from non-ionizing cancer diagnosis and pharmaceutical characterization to non-destructive artifact testing. Contemporary terahertz imaging systems typically rely on non-linear optical down-conversion of a fiber-based near-infrared femtosecond laser, requiring complex optical systems. Here, we demonstrate hyperspectral imaging with chip-scale frequency combs based on terahertz quantum cascade lasers. The dual …
An efficient simulator for quantum systems is one of the original goals for the efforts to develop a quantum computer [1]. In recent years, synthetic dimension in photonics [2] have emerged as a potentially powerful approach for simulation that is free from the constraint of geometric dimensionality. Here we demonstrate a quantum-correlated synthetic crystal, based upon a coherently-controlled broadband quantum frequency comb produced in a chip-scale dynamically modulated lithium niobate microresonator. The time-frequency entanglement inherent with the comb modes significantly extends the dime…
Ultrafast light-matter interactions lead to optical-field-driven photocurrents with an attosecond-level temporal response. These photocurrents can be used to detect the carrier-envelope-phase (CEP) of short optical pulses, and could be utilized to create optical-frequency, petahertz (PHz) electronics for information processing. Despite recent reports on optical-field-driven photocurrents in various nanoscale solid-state materials, little has been done in examining the large-scale integration of these devices. In this work, we demonstrate enhanced, on-chip CEP detection via optical-field-driven…
We demonstrate a robust low-loss optical interface by tiling passive (i.e., without doping of active ions) thin film lithium niobate (TFLN) and active (i.e., doped with rare earth ions) TFLN substrates for monolithic integration of passive/active lithium niobate photonics. The tiled substrates composed of both active and passive areas allow to pattern the mask of the integrated active passive photonic device at once using a single continuous photolithography process. The interface loss of tiled substrate is measured as low as 0.26 dB. Thanks to the stability provided by this approach, a four-c…
Scalable quantum photonic technologies require low-loss integration of many identical single-photon sources with photonic circuitry on a chip. Relatively complex quantum photonic circuits have already been demonstrated; however, sources used so far relied on parametric-down-conversion. Hence, the efficiency and scalability are intrinsically limited by the probabilistic nature of the sources. Quantum emitter-based single-photon sources are free of this limitation, but frequency matching of multiple emitters within a single circuit remains a challenge. In this work, we demonstrate a key componen…
A micro-ring-resonator (MRR) optical biosensor based on the evanescent field sensing mechanism has been extensively studied due to its high sensitivity and compact device size. However, a suitable on-chip integrated spectrometer device has to be demonstrated for the lab-on-a-chip applications, which can read the resonance wavelength shift from MRR biosensors based on minuscule changes in refractive index. In this paper, we demonstrated the design and experimental results of the near-infrared lab-on-a-chip optical biosensor platform that monolithically integrates the MRR and the on-chip spectro…
Microwave photonics uses light to carry and process microwave signals over a photonic link. However, light can instead be used as a stimulus to microwave devices that directly control microwave signals. Such optically controlled amplitude and phase-shift switches are investigated for use in reconfigurable microwave systems, but they suffer from large footprint, high optical power level required for switching, lack of scalability and complex integration requirements, restricting their implementation in practical microwave systems. Here, we report Monolithic Optically Reconfigurable Integrated M…
