Recent advances and emerging directions in terahertz biophotonics

Abstract Since the early 2000s, numerous studies have been conducted on the application of terahertz (THz) biophotonics. Despite steady advances, its adoption has remained substantially behind that of optical technologies. This disparity arises from several critical limitations for biological measurements, including (i) spatial resolution, (ii) sensitivity, (iii) imaging speed, and (iv) system compactness. These constraints often lead to unreliable data and hinder practical implementation. Addressing these challenges is essential for meaningful progress in the field. Recent developments in THz techniques have enabled direct visualization of cells and biomolecules, indicating significant potential for future applications. This review summarizes current efforts to address these limitations, outlines key historical developments, and discusses prospective directions toward the broader implementation of THz biophotonics.