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Fast and accurate detection of light in the near-infrared (NIR) spectral range plays a crucial role in modern society, from alleviating speed and capacity bottlenecks in optical communications to enhancing the control and safety of autonomous vehicles through NIR imaging systems. Several technological platforms are currently under investigation to improve NIR photodetection, aiming to surpass the performance of established III-V semiconductor p-i-n (PIN) junction technology. These platforms include in situ-grown inorganic nanocrystals and nanowire arrays, as well as hybrid organic-inorganic materials such as graphene-perovskite heterostructures. However, challenges remain in nanocrystal and nanowire growth, large-area fabrication of high-quality 2D materials, and the fabrication of devices for practical applications. Here, we explore the potential for tailored semiconductor nanocrystals to enhance the responsivity of planar metal-semiconductor-metal (MSM) photodetectors. MSM technology offers ease of fabrication and fast response times compared to PIN detectors. We observe enhancement of the optical-to-electric conversion efficiency by up to a factor of ~2.5 through the application of plasmonically-active semiconductor nanorods and nanocrystals. We present a protocol for synthesizing and rapidly testing the performance of non-stoichiometric tungsten oxide (WO$_{3-x}$) nanorods and cesium-doped tungsten oxide (Cs$_y$WO$_{3-x}$) hexagonal nanoprisms prepared in colloidal suspensions and drop-cast onto photodetector surfaces. The results demonstrate the potential for a cost-effective and scalable method exploiting tailored nanocrystals to improve the performance of NIR optoelectronic devices.

In this study, we address challenges in designing quantum information processors based on electron spin qubits in electrostatically-defined quantum dots (QDs). Numerical calculations of charge stability diagrams are presented for a realistic double QD device geometry. These methods generaize to linear QD arrays, and are based on determining the effective parameters of a Hubbard model Hamiltonian that is then diagonalized to find the many-electron ground state energy. These calculations enable the identification of gate voltage ranges that maintain desired charge states during qubit manipulation, and also account for electrical cross-talk between QDs. As a result, the methods presented here promise to be a valuable tool for developing scalable spin qubit quantum processors., Comment: 10 pages, 4 figures. Submitted in proceedings of the VI Applied Mathematics, Modeling, and Computer Simulation (AMMCS) International Conference, Waterloo, Ontario, Canada

We present a unitary control pulse design method for a scalable quantum computer architecture based on electron spins in lateral quantum dots. We employ simultaneous control of spin interactions and derive the functional forms of spin Hamiltonian parameter pulses for a universal set of 1- and 2-qubit logic gates. This includes selective spin rotations with the weak local g-factor variations in the presence of the global oscillating field, and a Control-Phase operation with the simultaneous control of g-factors and exchange couplings. We outline how to generalize the control scheme to multiqubit gate operations and the case of constrained or imperfect control of the Hamiltonian parameters., Comment: 10 pages, 2 figures, 1 table. Submitted in proceedings of the VI Applied Mathematics, Modeling, and Computer Simulation (AMMCS) International Conference, Waterloo, Ontario, Canada