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<jats:p> <jats:italic>We study a homogeneous two-component dipolar Fermi gas with 1D spin-orbit coupling (SOC) at zero temperature and find that the system undergoes a transition from the paramagnetic phase to the ferromagnetic phase under suitable dipolar interaction constant <jats:italic>λ</jats:italic> <jats:sub>d</jats:sub>, SOC constant <jats:italic>λ</jats:italic> <jats:sub>SOC</jats:sub> and contact interaction constant <jats:italic>λ</jats:italic> <jats:sub>s</jats:sub>. This phase transition can be of either 1st order or 2nd order, depending on the parameters. Near the 2nd-order phase transition, the system is partially magnetized in the ferromagnetic phase. With SOC, the ferromagnetic phase can even exist in the absence of the contact interaction. The increase in dipolar interaction, SOC strength, and contact interaction are all helpful to stabilize the ferromagnetic state. The critical dipolar interaction strength at the phase transition can be reduced by the increase in SOC strength or contact interaction. Phase diagrams of these systems are obtained.</jats:italic> </jats:p>

<jats:p> <jats:italic>The spin qubit in quantum dots is one of the leading platforms for quantum computation. A crucial requirement for scalable quantum information processing is the high efficient measurement. Here we analyze the measurement process of a quantum-dot spin qubit coupled to a superconducting transmission line resonator. Especially, the phase shift of the resonator is sensitive to the spin states and the gate operations. The response of the resonator can be used to measure the spin qubit efficiently, which can be extend to read out the multiple spin qubits in a scalable solid-state quantum processor.</jats:italic> </jats:p>

<jats:p> <jats:italic>Isolated attosecond pulses with a duration of 88 as are generated in the spectral range of 29–72 eV using double optical gating technique. The gate width is set to be shorter than half the optical cycle to avoid carrier envelop phase stabilization of the 4.2 fs driving laser pulses centered at 800 nm. The attosecond pulse duration is measured with the technique of frequency resolved optical gating for complete reconstruction of attosecond bursts.</jats:italic> </jats:p>

<jats:p> <jats:italic>We investigate the electron capture processes of N<jats:sup>4+</jats:sup>(1<jats:italic>s</jats:italic> <jats:sup>2</jats:sup>2<jats:italic>s</jats:italic>) colliding with He(1<jats:italic>s</jats:italic> <jats:sup>2</jats:sup>) in the energy range of 10–1700 eV/amu using the quantum-mechanical molecular-orbital close-coupling (QMOCC) method. Total and state-selective single-electron capture and double-electron capture (SEC and DEC) cross sections are obtained and compared with other available studies. The results agree better with the experimental data in both trend and magnitude when the electron translation factor (ETF) effects are included. Our results indicate that both the SEC and DEC processes play important roles in the considered energy region. For the SEC processes, the N<jats:sup>3+</jats:sup>(1<jats:italic>s</jats:italic> <jats:sup>2</jats:sup>2<jats:italic>p</jats:italic> <jats:sup>2</jats:sup>) + He<jats:sup>+</jats:sup>(1<jats:italic>s</jats:italic>) states are the dominant capture states, and the N<jats:sup>2+</jats:sup>(1<jats:italic>s</jats:italic> <jats:sup>2</jats:sup>2<jats:italic>s</jats:italic>2<jats:italic>p</jats:italic> <jats:sup>2</jats:sup>) + He<jats:sup>2+</jats:sup> states are the main DEC states.</jats:italic> </jats:p>

<jats:p> <jats:italic>The spider structure in the photoelectron momentum distributions (PMDs) of ionized electrons from the hydrogen atom is simulated by solving the time-dependent Schrödinger equation (TDSE). We find that the spider structure exhibits sensitive dependence on carrier envelope phase (CEP) of the few-cycle pulses. To elucidate the striking CEP dependence of the spider structure, we select three physical parameters <jats:italic>I</jats:italic> <jats:sub>L</jats:sub>, <jats:italic>I</jats:italic> <jats:sub>R</jats:sub>, and <jats:italic>I</jats:italic> <jats:sub>R</jats:sub>/<jats:italic>I</jats:italic> <jats:sub>L</jats:sub> to quantitatively characterize the variations of the spider structure induced by altering the CEPs. <jats:italic>I</jats:italic> <jats:sub>L</jats:sub> is the sum of the left half panel of the transverse cut curves (i.e., the sum of all the negative momenta along the laser polarization direction), <jats:italic>I</jats:italic> <jats:sub>R</jats:sub> is the sum of the right half panel of the transverse cut curves (i.e., the sum of all the positive momenta along the laser polarization direction), and <jats:italic>I</jats:italic> <jats:sub>R</jats:sub>/<jats:italic>I</jats:italic> <jats:sub>L</jats:sub> is the ratio between the two sums. These parameters are shown to have monotonic relation with the CEP value, which is exploited to extract the CEPs. We anticipate that our method will be useful for obtaining CEPs encoded in the spider structure of PMDs.</jats:italic> </jats:p>

<jats:p> <jats:italic>When light travels in biological tissues, it undergoes multiple scattering and forms speckles, which seriously restricts the penetration depth of optical imaging in biological tissues. With wavefront shaping method, by modulating the wavefront of incident light to compensate for the wavefront aberration, light focusing and scanning imaging through scattering media can be achieved. However, wavefront shaping must be accomplished within the speckle decorrelation time. Considering the short speckle decorrelation time of living tissues, the speed of wavefront shaping is rather essential. We propose a new iterative optimization wavefront shaping method to improve the speed of wavefront shaping in which the existing parallel optimization wavefront shaping method is improved and is combined with the superpixel method. Compared with the traditional multi-frequency parallel optimization method, the modulation rate of our method is doubled. Moreover, we combine the high frame rate amplitude modulator, i.e., the digital micromirror device (DMD), with the superpixel method to replace the traditional phase modulator (i.e., spatial light modulator), which further increases the optimization speed. In our experiment, when the number of the optical modes is 400, light focusing is achieved with only 1000 DMD superpixel masks and the enhancement factor reaches 223. Our approach provides a new path for fast light focusing through wavefront shaping.</jats:italic> </jats:p>

<jats:p> <jats:italic>III–V quantum dot (QD) lasers monolithically grown on CMOS-compatible Si substrates are considered as essential components for integrated silicon photonic circuits. However, epitaxial growth of III–V materials on Si substrates encounters three obstacles: mismatch defects, antiphase boundaries (APBs), and thermal cracks. We study the evolution of the structures on U-shaped trench-patterned Si (001) substrates with various trench orientations by homoepitaxy and the subsequent heteroepitaxial growth of GaAs film. The results show that the formation of (111)-faceted hollow structures on patterned Si (001) substrates with trenches oriented along [110] direction can effectively reduce the defect density and thermal stress in the GaAs/Si epilayers. The (111)-faceted silicon hollow structure can act as a promising platform for the direct growth of III–V materials for silicon based optoelectronic applications</jats:italic>.</jats:p>

<jats:p> <jats:italic>Taking the long-wavelength Rayleigh–Taylor instability (RTI) on the thin shell of inertial confinement fusion as the research object, a linear analytical model is presented to study the phase effects that are caused by the phase difference of single-mode perturbations on the two interfaces. Its accuracy is tested by numerical simulations. By analyzing the characteristic of this model, it is found that the phase difference does not change the basic RTI structure (only one spike and one bubble in a period). However, the symmetry of the spike and bubble is destroyed, which has non-expected influences on the convergent motion of ICF targets. Meanwhile, the phenomenon that the distance between spikes and bubbles along the vertical direction of acceleration differs by <jats:italic>π</jats:italic> is demonstrated. It is also shown that when the phase difference is large, the temporal evolution of the RTI is more serious and the thin target is easier to tend to break</jats:italic>.</jats:p>

<jats:p> <jats:italic>New stable stoichiometries in K–Ga systems are firstly investigated up to 100 GPa by the unbiased structure searching techniques. Six novel compositions as K<jats:sub>4</jats:sub>Ga, K<jats:sub>3</jats:sub>Ga, K<jats:sub>2</jats:sub>Ga, KGa, KGa<jats:sub>2</jats:sub> and KGa<jats:sub>4</jats:sub> are found to be thermodynamically stable under pressure. Most of the predicted stable phases exhibit metallic character, while the</jats:italic> <jats:inline-formula> <jats:tex-math> <?CDATA $Fd\bar{3}m$?> </jats:tex-math> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mi>F</mml:mi> <mml:mi>d</mml:mi> <mml:mover accent="true"> <mml:mn>3</mml:mn> <mml:mo>¯</mml:mo> </mml:mover> <mml:mi>m</mml:mi> </mml:mrow> </mml:math> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="cpl_37_2_026201_ieqn1.gif" xlink:type="simple" /> </jats:inline-formula> <jats:italic>KGa phase behaves as a semiconductor with a bandgap ∼1.62 eV. Notably, the gallium atoms exhibit different interesting morphologies; e.g., Ga<jats:sub>2</jats:sub> units, zigzag chains, six rings and cage. We further investigate the bonding nature of K–Ga systems with help of electron localization function and Bader charge analyses. Strong covalent bonding characteristics are found between the Ga and Ga atoms, and ionic bonding patterns are observed between the K and Ga atoms. Meanwhile, we notice charge transferring from the K atom to the Ga atom in the K–Ga systems. The present results can be helpful for understanding the diverse structures and properties of K–Ga binary compounds at high pressures</jats:italic>.</jats:p>

<jats:p> <jats:italic>PbZr<jats:sub>x</jats:sub>Ti<jats:sub>1–x</jats:sub>O<jats:sub>3</jats:sub> (PZT) films are fabricated on F-doped tin oxide (FTO) substrates using chemical solutions containing PVP polymer and rapid thermal annealing processing. The dependence of the layered PZT multilayer formation and their optical properties on the Zr content x are examined. It is found that all the PZT films are crystallized and exhibit 110-preferred orientation. When x varies in the region of 0–0.8, the PZT films display lamellar structures, and a high reflection band occurs in each optical reflectance spectrum curve. Especially, those PZT films with Zr/Ti atomic ratio of 35/65–65/35 show clearly layered cross-sectional morphologies arranged alternatively by porous and dense PZT layers, and have a peak optical reflectivity of &gt;70% and a band width of &gt;45 nm. To obtain the optimal Bragg reflection performance of the PZT multilayers, the Zr content should be selected in the range of 0.35–0.65</jats:italic>.</jats:p>