Implementation of an error-corrected quantum computer is believed to require a quantum processor with a million or more physical qubits, and, in order to run such a processor, a quantum control system of similar scale will be required. Such a controller will need to be integrated within the cryogenic system and in close proximity with the quantum processor in order to make such a system practical. Here, we present a prototype cryogenic CMOS quantum controller designed in a 28-nm bulk CMOS process and optimized to implement a 16-word (4-bit) XY gate instruction set for controlling transmon qubits. After introducing the transmon qubit, including a discussion of how it is controlled, design considerations are discussed, with an emphasis on error rates and scalability. The circuit design is then discussed. Cryogenic performance of the underlying technology is presented, and the results of several quantum control experiments carried out using the integrated controller are described. This article ends with a comparison to the state of the art and a discussion of further research to be carried out. It has been shown that the quantum control IC achieves promising performance while dissipating less than 2 mW of total ac and dc power and requiring a digital data stream of less than 500 Mb/s.

Solar electricity is more expensive than that produced by traditional sources. But over the past two decades, the cost gap has been closing. Solar photovoltaic (SPV) technology has emerged as a useful power source of applications such as lightning, meeting the electricity needs of villages, hospitals, telecommunications, and houses. The long and increasing dominance of crystalline silicon in photovoltaic (PV) market is perhaps surprising given the wide variety of materials capable of producing the photovoltaic effect. PV based on silicon wafers has captured more than 90% market share because it is more reliable and generally more efficient than competing technologies. The crystalline silicon PV is reliable as far as long term stability in real field but it is not economically viable due to starting material silicon itself costly. But still, research continues on developing a diverse set of alternative photovoltaic technology. Now PV technology is being increasingly recognized as a part of the solution to the growing energy challenge and an essential component of future global energy production. In this paper, we give a brief review about PV technology particularly crystalline silicon PV including the world and Indian PV scenarios.

Novel Diamond-like Nanocomposite (DLN) thin film as Anti-Reflective Nanocomposite Based (ARNAB) coating for crystalline silicon (c-Si) solar cell is the main objective of this paper. The DLN film was deposited by plasma assisted chemical vapour deposition (PACVD) method and characterized by Fourier transform infrared, field emission scanning electron microscope, and high resolution transmission emission microscope. Results show that c-Si3N4 and c-SiC nanoparticle (3–5 nm) were embedded in a-C:H matrix, and they were interpenetrated by Si-C bonding, i.e., typical DLN structure. The optical properties of the film were investigated by UV-VIS-near-infrared and photoluminescence spectroscopy. The performance of ARNAB coating was evaluated by measuring the reflectance, external quantum efficiency (EQE), and conversion efficiency. The solar weighted average reflection from textured c-Si was reduced to 2.25% in wavelength range 300 nm–1100 nm, and more than 90% EQE of the solar cell was achieved within the broad wavelength range 560 nm–870 nm. The result has been also compared with conventional silicon nitride anti-reflection coating (ARC). Finally, 0.8% absolute increased of efficiency was achieved with ARNAB layer in comparison with silicon nitride AR coating. The ARNAB thin film has a great potential to be used as ARC for silicon based solar cell.

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