Manipulation of Helicity-Dependent Photocurrent and Stokes Parameter Detection in Topological Insulator BiTe Nanowires.

Helicity-dependent photocurrent (HDPC) and its modulation in topological insulator BiTe nanowires have been investigated. It is revealed that when the incident plane of a laser is perpendicular to the nanowire, the HDPC is an odd function of the incident angle, which is mainly contributed by the circular photogalvanic effect originating from the surface states of BiTe nanowire. When the incident plane of a laser is parallel to the nanowire, the HDPC is approximately an even function of the incident angle, which is due to the circular photon drag effect coming from the surface states.

Electric Control of Helicity-Dependent Photocurrent and Surface Polarity Detection on Two-Dimensional BiOSe Nanosheets.

Bismuth oxyselenide (BiOSe) is a two-dimensional (2D) layered semiconductor material with high electron Hall mobility and excellent environmental stability as well as strong spin-orbit interaction (SOI), which has attracted intense attention for application in spintronic and spin optoelectronic devices. However, a comprehensive study of spin photocurrent and its microscopic origin in BiOSe is still missing. Here, the helicity-dependent photocurrent (HDPC) was investigated in BiOSe nanosheets.

Tuning spin-orbit coupling and realizing inverse persistent spin helix by an extra above-barrier radiation in a GaAs/AlGaAs heterostructure.

A persistent spin helix with equal strength of the Rashba and Dresselhaus spin-orbit coupling (SOC) is expected for future spintronic devices due to the suppression of spin relaxation. In this work we investigate the optical tuning of the Rashba and Dresselhaus SOC by monitoring the spin-galvanic effect (SGE) in a GaAs/AlGaAs two dimensional electron gas. An extra control light above the bandgap of the barrier is introduced to tune the SGE excited by a circularly polarized light below the bandgap of GaAs.

Local Electric-Field-Induced Spin Photocurrent in ReS.

A spin-related photocurrent excited by circularly polarized light is observed near the electrodes on a few-layer ReS sample at room temperature. For both electrodes, the spatial distribution of the spin photocurrent shows a feature of two wings, with one positive and the other negative. In this work, it is suggested that this phenomenon arises from the inverse spin Hall effect due to the local electric field near the electrode.

Identification of the molecular subtype and prognostic characteristics of pancreatic cancer based on CD8 + T cell-related genes.

CD8 + T lymphocytes are immune cells that play a crucial anti-tumor role in the human body, and prognostic value of CD8 + T cell-related regulatory genes in PAAD remains elusive. Data on 179 expression profiles across 13 immune cell datasets were downloaded from the GEO database, and the expression profiles of CD8 + T cell-related genes were obtained using WGCNA. Molecular subtypes based on CD8 + T cell-related genes were constructed using the ConsensusClusterPlus algorithm.

Giant photoinduced inverse spin Hall effect of the surface states in three dimensional topological insulators BiTe with different thickness.

The photoinduced inverse spin Hall effect (PISHE) has been studied in three dimensional (3D) topological insulator (TI) BiTe thin films with different thicknesses (3, 5, 12 and 20 quintuple layer (QL)). The sign of the PISHE current flips only once in the 3- and 20-QL BiTe films, but it flips three times in the 5-, 7- and 12-QL samples. The three-times sign flip is due to the superposition of the PISHE current of the top and bottom surface states in BiTe films.

Current-Induced Spin Photocurrent in GaAs at Room Temperature.

Circularly polarized photocurrent, observed in p-doped bulk GaAs, varies nonlinearly with the applied bias voltage at room temperature. It has been explored that this phenomenon arises from the current-induced spin polarization in GaAs. In addition, we found that the current-induced spin polarization direction of p-doped bulk GaAs grown in the (001) direction lies in the sample plane and is perpendicular to the applied electric field, which is the same as that in GaAs quantum well.

Systematic Analysis of an Invasion-Related 3-Gene Signature and Its Validation as a Prognostic Model for Pancreatic Cancer.

Background: Pancreatic adenocarcinoma (PAAD) is a malignant tumor of the digestive system that is associated with a poor prognosis in patients owing to its rapid progression and high invasiveness.

Methods: Ninety-seven invasive-related genes obtained from the CancerSEA database were clustered to obtain the molecular subtype of pancreatic cancer based on the RNA-sequencing (RNA-seq) data of The Cancer Genome Atlas (TCGA). The differentially expressed genes (DEGs) between subtypes were obtained using the limma package in R, and the multi-gene risk model based on DEGs was constructed by Lasso regression analysis.

Identification and clinical validation of EMT-associated prognostic features based on hepatocellular carcinoma.

Background: The aim of this study was to construct a model based on the prognostic features associated with epithelial-mesenchymal transition (EMT) to explore the various mechanisms and therapeutic strategies available for the treatment of metastasis and invasion by hepatocellular carcinoma (HCC) cells.

Methods: EMT-associated genes were identified, and their molecular subtypes were determined by consistent clustering analysis. The differentially expressed genes (DEGs) among the molecular subtypes were ascertained using the limma package and they were subjected to functional enrichment analysis.

Systematic Characterization of Novel Immune Gene Signatures Predicts Prognostic Factors in Hepatocellular Carcinoma.

The prognosis of patients with hepatocellular carcinoma (HCC) is negatively affected by the lack of effective prognostic indicators. The change of tumor immune microenvironment promotes the development of HCC. This study explored new markers and predicted the prognosis of HCC patients by systematically analyzing immune characteristic genes.

Multidetector computed tomography three-dimensional and multiplanar reconstruction diagnosis of a rare cause of gastrointestinal bleeding: A case report.

Background: Anastomosis of the testicular vein with the superior mesenteric vein rarely causes severe gastrointestinal bleeding. To date, there have been few studies describing its appearance on medical imaging. Here, we present multidetector computed tomography three-dimensional and multiplanar reconstruction (MPR) images of a typical digital subtraction angiography showing proven ectopic bleeding and provide the first review of the image performance.

Efficacy and Safety of Androgen-Deprivation Therapy Combined with Docetaxel Plus Prednisone in High-Burden Metastatic Hormone-Sensitive Prostate Cancer.

Purpose: The aim of this study was to evaluate the efficacy and safety of hormonal and synchronous docetaxel plus prednisone (DocP) in metastatic hormone-sensitive prostate cancer (mHSPC).

Methods: One hundred fifty-one cases with high-burden mHSPC diagnosed at 1 single center from January 2014 to August 2018 were analyzed retrospectively. Among them, 85 cases received androgen-deprivation therapy (ADT) within 3 months, along with 6 cycles of docetaxel + prednisone (treatment group), whereas 66 received ADT alone (control group).

Control of Circular Photogalvanic Effect of Surface States in the Topological Insulator BiTe via Spin Injection.

The circular photogalvanic effect (CPGE) provides a method utilizing circularly polarized light to control spin photocurrent and will also lead to novel opto-spintronic devices. The CPGE of three-dimensional topological insulator BiTe with different substrates and thicknesses has been systematically investigated. It is found that the CPGE current can be dramatically tuned by adopting different substrates.

Nonfullerene Ternary Organic Solar Cell with Effective Charge Transfer between Two Acceptors.

High power conversion efficiency can be realized by using a ternary bulk heterojunction with complementary absorption spectra in organic solar cells. However, as the development of nonfullerene acceptors with a broad absorption spectrum makes the absorption efficiency of the photovoltaic devices close to optimal, such a strategy needs modifying. In particular, charge transfer between the two acceptors is necessary to be considered.

Insights into Charge Separation and Transport in Ternary Polymer Solar Cells.

Although ternary polymer solar cells have more potential in realizing a high power conversion efficiency than the binary counterparts, the mechanism of exciton separation and charge transport in such complicated ternary systems is far from being understood. Herein, we focus on this issue and give a clear view on the detailed roles of the ternary components contributing to the device performance, through utilizing the technique of pump-probe photoconductivity spectroscopy combined with transient photoluminescence spectroscopy, for the first time for ternary polymer solar cells. The ternary photovoltaic devices are based on PBDB-T:ITIC:PCBM and present a dramatic improvement in efficiency in comparison to that of the binary counterparts.

Observation of Extrinsic Photo-Induced Inverse Spin Hall Effect in a GaAs/AlGaAs Two-Dimensional Electron Gas.

The inverse spin Hall effect induced by circularly polarized light has been observed in a GaAs/AlGaAs two-dimensional electron gas. The spin transverse force has been determined by fitting the photo-induced inverse spin Hall effect (PISHE) current to a theoretical model. The PISHE current is also measured at different light power and different light spot profiles, and all the measurement results are in good agreement with the theoretical calculations.

Ferroelectric Field Effect Induced Asymmetric Resistive Switching Effect in BaTiO/Nb:SrTiO Epitaxial Heterojunctions.

Asymmetric resistive switching processes were observed in BaTiO/Nb:SrTiO epitaxial heterojunctions. The SET switching time from the high-resistance state to low-resistance state is in the range of 10 ns under + 8 V bias, while the RESET switching time from the low-resistance state to high-resistance state is in the range of 10 ns under - 8 V bias. The ferroelectric polarization screening controlled by electrons and oxygen vacancies at the BaTiO/Nb:SrTiO heterointerface is proposed to understand this switching time difference.

Inverse spin Hall effect induced by linearly polarized light in the topological insulator BiSe.

The inverse spin Hall effect (ISHE) induced by the normal incidence of linearly-polarized infrared radiation has been observed in the topological insulator BiSe. A model has been proposed to explain the phenomenon, and the spin transverse force has been determined by the model fitting. The anomalous linear photogalvanic effect (ALPGE) is also observed, and the photoinduced momentum anisotropy is extracted.

Photoinduced Inverse Spin Hall Effect of Surface States in the Topological Insulator BiSe.

The three-dimensional (3D) topological insulator (TI) BiSe exhibits topologically protected, linearly dispersing Dirac surface states (SSs). To access the intriguing properties of these SSs, it is important to distinguish them from the coexisting two-dimensional electron gas (2DEG) on the surface. Here, we use circularly polarized light to induce the inverse spin Hall effect in a BiSe thin film at different temperatures (i.

Observation of spin-polarized photoconductivity in (Ga,Mn)As/GaAs heterojunction without magnetic field.

In the absent of magnetic field, we have observed the anisotropic spin polarization degree of photoconduction (SPD-PC) in (Ga,Mn)As/GaAs heterojunction. We think three kinds of mechanisms contribute to the magnetic related signal, (i) (Ga,Mn)As self-producing due to the valence band polarization, (ii) unequal intensity of left and right circularly polarized light reaching to GaAs layer to excite unequal spin polarized carriers in GaAs layer, and (iii) (Ga,Mn)As as the spin filter layer for spin transport from GaAs to (Ga,Mn)As. Different from the previous experiments, the influence coming from the Zeeman splitting induced by an external magnetic field can be avoided here.

Tuning of Rashba/Dresselhaus Spin Splittings by Inserting Ultra-Thin InAs Layers at Interfaces in Insulating GaAs/AlGaAs Quantum Wells.

The ratio of Rashba and Dresselhaus spin splittings of the (001)-grown GaAs/AlGaAs quantum wells (QWs), investigated by the spin photocurrent spectra induced by circular photogalvanic effect (CPGE) at inter-band excitation, has been effectively tuned by changing the well width of QWs and by inserting a one-monolayer-thick InAs layer at interfaces of GaAs/AlGaAs QWs. Reflectance difference spectroscopy (RDS) is also employed to study the interface asymmetry of the QWs, whose results are in good agreement with that obtained by CPGE measurements. It is demonstrated that the inserted ultra-thin InAs layers will not only introduce structure inversion asymmetry (SIA), but also result in additional interface inversion asymmetry (IIA), whose effect is much stronger in QWs with smaller well width.

Reflectance difference spectroscopy microscope for circular defects on InN films.

Reflectance difference spectroscopy microscope (μ-RDS) is presented to characterize microstructural defects on the surface of materials. We use this microscope to study the circular defects on InN films and obtain the real normal reflectivity image and reflectance difference (RD) image by averaging the results before and after a 90° rotation of the sample. We analyze the experimental data along with other methods and formally ensure the reliability of this microscope.

Spin transport in undoped InGaAs/AlGaAs multiple quantum well studied via spin photocurrent excited by circularly polarized light.

The spin diffusion and drift at different excitation wavelengths and different temperatures have been studied in undoped InGaAs/AlGaAs multiple quantum well (MQW). The spin polarization was created by optical spin orientation using circularly polarized light, and the reciprocal spin Hall effect was employed to measure the spin polarization current. We measured the ratio of the spin diffusion coefficient to the mobility of spin-polarized carriers.