Interlayer coupling is a central knob for engineering electronic reconstruction and energy dissipation in van der Waals heterostructures. However, a unified understanding that connects interlayer coupling to both electrical and thermal responses is still lacking. Electron–phonon coupling (EPC) could bridge this gap by linking interlayer coupling to both momentum and energy relaxation. Here we establish an electron–phonon-coupling-linked interpretation in MoS2/CrOCl heterostructures, where interlayer coupling-driven interfacial charge transfer reshapes the MoS2 electronic structure and, at the same time, renormalizes electron–phonon interactions that govern momentum relaxation and carrier–lattice energy relaxation. By using Raman and second-harmonic-generation (SHG) fingerprints, we identify 2L-MoS2/CrOCl as the strongest coupling configuration. This is evidenced by the largest change in mode separation of 1.29 cm−1 and a pronounced SHG suppression from 100% to 11.9% relative to pristine MoS2. In this regime, interfacial charge redistribution downshifts the MoS2 Fermi level and converts its native n-type character to p-type conduction. Along with electrical transport experiments, we also study the thermal transport and characterize the steady-state temperature rise through scanning thermal microscopy. The MoS2/CrOCl heterostructure exhibits more efficient heat evacuation, reducing the temperature rise by 38.5% under identical thermal loading conditions compared with the situation for pristine MoS2 on SiO2/Si. According to the observed EPC-linked electron and phonon transport properties, interlayer coupling in MoS2/CrOCl heterostructure has induced both carrier-polarity inversion and enhanced interfacial heat dissipation, providing a basis for codesigning electro-thermal multifunctional devices.
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As the demand for reliable high-performance nanoelectronics grows, comprehensive research on time-resolved nanoscale thermal detection in operating devices is becoming urgent. Here, we employ scanning thermal microscopy (SThM) to investigate the real-time thermal response of graphene field-effect transistors (GFETs), further exhibiting their potential application in advanced electric-thermal communication. Revealed by in situ nanoscale temperature images, the full width at half maximum of hotspot in the GFET channel is 700 nm approximately, approaching the diffraction limit of traditional optics. The average temperature of device channel is proportional to the electric power from gate voltage, which manipulates the carrier concentration. Furthermore, a controllable management to the hotspot distribution is achieved successfully by adjusting the gate voltage in GFET. Profited from precise characterization and effective control of thermal distribution, the thermal response of GFET under 100 Hz voltage modulation is real-time monitored via SThM. Notably, the thermal response speed of GFET reaches up to 1 ms during our measurement, empowering outstanding capability for electric-thermal communication across various frequency modulations. This rapid thermal response might be attributed to excellent thermal conductivity and low specific heat capacity of graphene. Our findings highlight the potential of SThM in rapid and sensitive thermal response detection based on graphene nanoelectronics, which also potentially opens up new possibilities for more efficient and precise electric-thermal communication in the future.
With the packing density growing continuously in integrated electronic devices, sufficient heat dissipation becomes a serious challenge. Recently, dielectric materials with high thermal conductivity have brought insight into effective dissipation of waste heat in electronic devices to prevent them from overheating and guarantee the performance stability. Layered CrOCl, an anti-ferromagnetic insulator with low-symmetry crystal structure and atomic level flatness, might be a promising solution to the thermal challenge. Herein, we have systematically studied the thermal transport of suspended few-layer CrOCl flakes by micro-Raman thermometry. The CrOCl flakes exhibit high thermal conductivities along zigzag direction, from ~ 392 ± 33 to ~ 1,017 ± 46 W·m−1·K−1 with flake thickness from 2 to 50 nm. Besides, pronounced thickness-dependent thermal conductivity ratio (
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