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We design and construct an ultrafast optical spectroscopy instrument that integrates both on-site in situ high-pressure technique and low-temperature tuning capability. Conventional related instruments rely on off-site tuning and calibration of the high pressure. Recently, we have developed an on-site in situ technique, which has the advantage of removing repositioning fluctuation. That instrument only works at room temperature, which greatly hampers its application to the investigation of correlated quantum materials. Here, we further integrate low temperature functioning to this instrument, by overcoming enormous technical challenges. We demonstrate on-site in situ high-pressure ultrafast spectroscopy under a tunable temperature, from liquid-helium to above-room temperatures. During the pressure and temperature tuning process, the sample neither moves nor rotates, allowing for reliable systematic pressure- and temperature-dependence data acquisition. Ultrafast dynamics under 10–60 GPa at 130 K, as well as 40–300 K at 15 GPa, is achieved. Increasing and decreasing pressure within 5–40 GPa range at 79 K has also been achieved. The precisions are 0.1 GPa and 0.1 K. Significantly, temperature-induced pressure drifting is overcome by our double-pneumatic membrane technique. Our low temperature on-site in situ system enables precise pressure and temperature control, opening the door for reliable investigation of ultrafast dynamics of excited quantum states, especially phase transitions in correlated materials, driven by both pressure and temperature. [ABSTRACT FROM AUTHOR]

C16H14Cl2N2O2, triclinic, P1‾ $P\overline{1}$ (no. 2), a = 8.9215(15) Å, b = 10.0013(15) Å, c = 10.5713(15) Å, α = 62.517(2)°, β = 75.325(2)°, γ = 68.9930(10)°, V = 776.8(2) Å3, Z = 2, Rgt (F) = 0.0417, wRref (F 2) = 0.1414, T = 296(2) K.

Black phosphorus (BP) has attracted great research interest in nonlinear optics due to its anisotropic photoelectronic properties. As an allotrope of phosphorus, violet phosphorus (VP) has higher stability and desirable wide bandgap than BP, broadening the potential applications of phosphorus in optoelectronics. Herein, the nonlinear optical responses of layered BP and VP over broad spectral range from 405 to 1064 nm are investigated by the spatial self‐phase modulation (SSPM) method. These results show that both BP and VP exhibit excellent broadband SSPM effects. They all have large nonlinear susceptibility value (up to ≈ 10−8 e.s.u.), except for a weaker value at the near‐infrared band. Moreover, the SSPM pattern formation time becomes significantly longer with increasing wavelength. Significantly, an all‐optical switching using a 532 nm beam to control a 1064 nm near‐infrared beam is realized based on the SSPM, which demonstrate that the nonlinear optical response of signal beam (1064 nm) can be improved by adjusting the intensity of controlling beam (532 nm). This study provides a fascinating foundation for future applications of phosphorus allotropes in broadband nonlinear photonics. [ABSTRACT FROM AUTHOR]

Electron–phonon coupling (EPC) and phonon–phonon scattering (PPS) are at the core of the microscopic physics mechanisms of vast quantum materials. However, to date, there are rarely reports that these two processes can be spatially separated, although they are usually temporally detached with different characteristic lifetimes. Here, by employing ultrafast spectroscopy to investigate the photo‐carrier ultrafast dynamics in a LaCoO3 thin film on a (100) SrTiO3 substrate, intriguing evidence is found that the two interactions are indeed spatially separated. The EPC mainly occurs in the thin film, whereas PPS is largely in the substrate, especially at the several atomic layers near the interface. Across‐interface penetration and decay of optical phonons into acoustic phonons thus naturally occur. An EPC strength λEg = 0.30 is also obtained and an acoustic phonon mode at 45.3 GHz is observed. The finding lays out a cornerstone for future quantum nano device designs. [ABSTRACT FROM AUTHOR]

Birefringence, which modulates the polarization of electromagnetic wave, has been commercially developed and widely used in modern photonics. Fostered by high-frequency signal processing and communications, feasible birefringence technologies operating in gigahertz (GHz) range are highly desired. Here, a coherent phonon-induced GHz optical birefringence and its manipulation in SrTiO3 (STO) crystals are demonsrated. With ultrafast laser pumping, the coherent acoustic phonons with low damping are created in the transducer/STO structures. A series of transducer layers are examined and the optimized one with relatively high photon-phonon conversion efficiency, i.e., semiconducting LaRhO3 film, is obtained. The most intriguing finding here is that, by virtue of high sensitivity to strain perturbation of STO, GHz optical birefringence can be induced by the coherent acoustic phonons and the birefringent amplitudes possess crystal orientation dependence. Optical manipulation of both coherent phonons and its induced GHz birefringence by double pump technique are also realized. These findings reveal an alternative mechanism of ultrafast optical birefringence control, and offer prospects for applications in high-frequency acoustic-optics devices. [ABSTRACT FROM AUTHOR]

Esophageal squamous cell carcinoma (ESCC) is a prevalent malignant tumor of the digestive tract with a low 5-year survival rate due to the lack of effective treatment methods. Although therapeutic monoclonal antibodies (mAbs) now play an important role in cancer therapy, effective targeted mAbs are still lacking for ESCC. B7-H3 is highly expressed in a variety of tumors and has emerged as a promising therapeutic target. Several mAbs against B7-H3 have advanced to clinical trials, but their development has not yet been pursued for ESCC. Here, we developed a humanized and Fc-engineered anti-B7H3 mAb 24F-Hu-mut2 and systematically evaluated its anti-tumor activity in vitro and in vivo. The 24F-Hu-mut2 was humanized and modified in Fc fragment to obtain stronger antibody-dependent cell-mediated cytotoxicity(ADCC) activity and nanomolar affinity. Furthermore, both of ESCC cell-derived xenograft (CDX) and patient-derived xenograft (PDX) mice models indicated that 24F-Hu-mut2 displayed potent in vivo anti-tumor activity. In addition, a computational docking model showed that the mAb bound to IgC1 and IgC2 domain of B7-H3, which is closer to the cell membrane. Consistently, our ELISA results verified the binding of 24F-Hu-WT and IgC1 and IgC2. Our results indicate that 24F-Hu-mut2 has significant anti-ESCC activity both in vitro and in vivo, and this monoclonal antibody may be a promising antibody against ESCC and other B7-H3 overexpressing tumors. [ABSTRACT FROM AUTHOR]