Publications Details
A biological microcavity laser
We have demonstrated a new semiconductor laser device that may be useful in high speed characterization of cell morphology for diagnosis of disease. This laser device has critical advantages over conventional cell fluorescence detection methods since it provides intense, monochromatic, low divergence light signals that are emitted from lasing modes confined by a cell. Further, the device integrates biological structures with semiconductor materials at the wafer level to reduce size and simplify cell preparation. This microcavity semiconductor laser comprises a vertical cavity surface-emitting semiconductor, to provide gain and feedback for light confined by cells, and a dielectric mirror to close the cavity. Transparent cells loaded into the cavity act as dielectric waveguides to define transverse electromagnetic modes. Light emitted from the microcavity can be resolved into narrow spectral modes, high-contrast/coherent light images, or time-dependent pulses that reveal cell morphology and size. We have used this laser device as a cytometer in two basic configurations. First, as a probe of individual cells by spectral analysis of cell modes. Second, as scanning cytometer for rapidly probing large numbers of cells by pulse height spectroscopy.