Wavelength-Invariant E-band Nanolasers Enabled by Area-Compensated Quasi-Bound States in the Continuum Metasurfaces

High-density photonic integrated circuits and on-chip optical interconnects require on-chip light sources with strict spectral stability. While all-dielectric quasi-bound states in the continuum offer a promising platform for compact nanolasers, the structural asymmetry required to excite high-Q modes inevitably induces severe resonance wavelength shifts, severely limiting their practical deployment. In this work, we propose a robust, CMOS-compatible device blueprint that employs a geometric area-compensation mechanism to completely decouple Q-factor tuning from wavelength variations. By systematically compensating for the air-hole volume altered during symmetry breaking, the typical 30 nm redshift is completely suppressed. Consequently, the resonance wavelength remains strictly pinned at approximately 1417.5 nm, falling squarely within the telecommunication E-band, while the Q-factor can be continuously tuned from 109 to 103. Crucially, the compensated design exhibits exceptional fabrication tolerance, confining wavelength fluctuations to approximately 1.8 nm even under realistic modern fabrication errors, including up to 3% area deviation and up to 5° sidewall-angle deviation. Furthermore, we validate the active performance of this design through rigorous device-level numerical experiments. Using a custom three-dimensional FDTD solver coupled with a four-level atomic gain model, we demonstrate that these wavelength-invariant qBIC metasurfaces can sustain highly stable, single-mode E-band lasing. This approach provides a highly reliable framework for precision spectral control in advanced optical communication components.