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In advanced spectroscopy, the classical symmetric optical frequency comb is limited in temporal flexibility and selection freedom, which constrains the efficiency and stability of quantum manipulation. To overcome this limitation, we propose a method to realize precise energy-level manipulation using a femtosecond non-temporally symmetric optical frequency comb in the semiclassical three-level system. Numerical calculations show that the fall time of the pulse is the key parameter to realize the precise manipulation, and a shorter fall time contributes to the efficient accumulation of population. By optimizing the pulse parameters, 99.15% accumulation of population in the target state can be successfully achieved and stably maintained using an asymmetric slowly turned-on and rapidly turned-off (STRT) pulse train. Our demonstration of the non-temporally symmetric optical frequency comb provides a promising approach to efficient quantum-state preparation using spectral modulation.

To explore the strong coupling between surface phonon polaritons (SPhPs) and quantum dots in one-dimensional periodic microstructures for quantum information processing, we establish a comprehensive theoretical model for SPhPs at air–polar dielectric interfaces. By rigorously deriving the dispersion relations, we reveal the decisive role of scale effects on bandgap formation: continuous spectra without bandgaps emerge at the nanoscale (d∼10–100 nm), whereas periodic modulation induces significant Bloch mode folding and tunable bandgaps (0.5–5 μm width) at the microscale (d∼1–10 μm). Based on Fourier bandwidth limitations, we determine optimal channel widths (Ly≥10 μm) for maintaining low-loss modes with energy deviations below 1%. Through electromagnetic field quantization, we obtain analytical expressions for SPhP mode amplitudes and quantum dot transition rates. Calculations demonstrate that in micrometer-scale CsI structures, spontaneous emission rates can be modulated significantly: suppressed to <0.1 times the free-space values within bandgaps (excited-state lifetimes extended to ∼10 ns) and enhanced 5–8 times at conduction band edges. Leveraging these characteristics, we propose a scheme for batch quantum state manipulation of 102–103 arrayed quantum dots via selective excitation of specific Bloch modes using controlled laser frequency and angle, enabling parallel single-qubit gates with theoretical fidelity > 99%. Compared with surface plasmon polariton schemes, our approach utilizes the low-loss infrared characteristics of SPhPs (Q∼100–1000, 1–2 orders higher) to reduce decoherence rates, offering a new pathway for room-temperature solid-state quantum computing and on-chip multi-node entanglement distribution.

Semiconductors are the backbone of modern technology, garnering decades of investment in high-quality materials and devices. Electron spin systems in semiconductors, including atomic defects and quantum dots, have been demonstrated in the last two decades to host quantum coherent spin qubits, often with coherent spin–photon interfaces and proximal nuclear spins. These systems are at the center of developing quantum technology. However, new material challenges arise when considering the isotopic composition of host and qubit systems. The isotopic composition governs the nature and concentration of nuclear spins, which naturally occur in leading host materials. These spins generate magnetic noise—detrimental to qubit coherence—but also show promise as local quantum memories and processors, necessitating careful engineering dependent on the targeted application. Reviewing recent experimental and theoretical progress toward understanding local nuclear spin environments in semiconductors, we show this aspect of material engineering as critical to quantum information technology. Graphical abstract

An alternative quantum approach to quasinormal modes is based on the very recently introduced formalism of generalized photon creation and annihilation operators. A prediction of a significant intensification in the rate of spontaneous photon triplet generation is predicted when this process occurs in resonators that allow modulation of vacuum field fluctuations. Incidentally, this viewpoint suggests a close connection between quantum optics and classical electromagnetism. The simple case of planar resonators is described, with an intended application in the optical domain. From an ab initio development, it is specifically shown that an enhancement by orders of magnitude may be reached, relative to the cases of unconfined media. To this end, TiO2 shows an excellent combination of linear and nonlinear optical properties that appears beneficial in designing a integrated quantum light source of entangled photon triplets. Furthermore, it is shown that the present general formalism can be applied to any electromagnetic structure. This might result in openings in the design of photonic devices, beyond the case of resonating structures and photon triplet generation. This includes emission processes, such as laser emission and various Raman scattering processes. It is anticipated that the generalized operators could be useful tools in designing advanced quantum technologies. Day by day, communication and computing technologies are progressing at a lightning speed, which is particularly true of the quantum version of these technologies (QIST). Increasingly, these technologies are emerging from unusual and sometimes bewildering quantum optical effects, which are based on exotic quantum physical theories. Here, we describe the unexpected role of vacuum fluctuations.

Purpose. Implementation of brief analytical review of the distinguished scientific achievements of the world scientists-physicists, awarded the Nobel Prize on physics for the period 2011-2015. Methodology. Scientific methods of collection, analysis and analytical treatment of scientific and technical information of world level in area of astrophysics, physics of elementary particles, physics of high energies, of modern theoretical and experimental physics. Results. The brief analytical review of the scientific openings and distinguished achievements of scientists-physicists is resulted in area of modern physical and technical problems which were marked the Nobel Prizes on physics for the period 2011-2015. Originality. Systematization is executed with exposition in the short concentrated form of the known scientific and technical materials, devoted opening of acceleration of expansion of Universe, creation of breach technologies of manipulation the quantum systems, theoretical discovery of mechanism of origin of mass of under-atomic particles, invention of effective power sources of light–blue light-emitting diodes and opening of neutrino oscillations. Practical value. Popularization and deepening of scientific and technical knowledges for students, engineers and technical specialists and research workers in area of modern theoretical and experimental physics, extending their scientific range of interests and cooperation in further development of scientific and technical progress in human society. References 17, figures 14. Key words: modern physics, distinguished achievements, speed-up expansion of Universe, technologies of manipulation of the quantum systems, mechanism of origin of the masses of under-atomic particles, energy saving sources of light, blue lightemitting diodes, neutrino oscillations.. [TEXT NOT REPRODUCIBLE IN ASCII]

This chapter provides an overview of the current main areas of research in molecular magnetism, through short fundamental descriptions, reference to more comprehensive reviews of subfields when available, and selected relevant examples, the choice of these latter obviously being a reflection of the authors' subjectivity. The term molecular nanomagnet (MNM) has been used to denote a large paramagnetic molecule, whether its magnetization relaxes slowly or not. Since the beginning of last decade, there have been an increased number of investigations focusing on the use of molecular and molecular‐based magnetic coordination compounds for cryogenic cooling through the magnetocaloric effect (MCE). This chapter summarizes the basic framework of the MCE, how it is experimentally determined, and what are the key parameters to design materials with optimized MCE properties. The quantum entanglement of the wave functions of different qubits within a quantum gate is another property inherent to quantum computing (QC).

Using a semiclassical description we study the motion of cold atoms in the field of a driven high-Q optical cavity, which supports several radiation field modes close to the atomic transition frequency. We present stochastic differential equations for the coupled particle and field dynamics. While the atoms influence the field as a time varying refractive index and loss the motion is governed by the light forces induced by the cavity field. Kinetic energy can be extracted from the particles through cavity dissipation. For sufficiently large detuning spontaneous emission plays a minor role and the cooling scheme should work for any particles with a suitable optical dipole moment. We derive analytic expressions for the friction force and the momentum diffusion to estimate the cooling rate and temperature and exhibit the scaling properties of the cooling as function of atom and mode number. For the case of degenerate modes we demonstrate the possibility to accurately reconstruct atomic trajectories from the measured output field distributions. Finally, as a second example we show that there are good prospects for implementation of the scheme using evanescent fields appearing in microoptical devices.

We give an overview of our experiments on the quantum and classical dynamics of atoms in an amplitude modulated standing wave - the quantum driven pendulum. Atoms are prepared in a magneto-optic trap or as a dilute Bose-Einstein condensate and subjected to a far detuned optical standing wave. We observe the occurrence of a bifurcation sequence in the parameter space of the quantum driven pendulum. We also observe dynamical tunnelling between two classically isolated states of motion. The tunnelling process is coherent and we see more than eight tunnelling periods.

Radio-frequency ion traps provide ideal conditions for storing and manipulating single particles and localize them with a precision far below their resonance wavelength. By combining an optical cavity with the excellent position control provided by the trap, we have implemented a completely deterministic coupling of ions and the electromagnetic field. In this system we can investigate single-particle cavity QED dynamics with a predefined interaction strength and interaction time, which is not possible in atom-based systems.

We have observed Raman, Rayleigh and recoil induced resonances (RIR) in a continuous beam of slow and cold cesium atoms extracted from a 2D MOT with the moving molasses technique. We use the RIR to measure the velocity distribution, therefore the average speed (0.6–4 m/s) and temperature (50–500 μK) of the atomic beam. Compared to time of flight (TOF), this technique has the advantage of being local, more sensitive in the low-velocity regime (ν< 1 m/s) and it gives access to transverse velocities and temperatures. It may be extended to measure atomic velocities in the 2D MOT source of the atomic beam. It is an additional tool to study and optimize the cooling, the extraction and the (transverse) post-cooling of slow atomic beams.