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Two-dimensional transition metal dichalcogenides (TMDs) provide fertile ground to study the interplay between dimensionality and electronic properties because they exhibit a variety of electronic phases,such as semiconducting,superconducting,charge density waves (CDW) states,and other unconventional physical properties.Compared with other classical TMDs,such as Mort insulator 1T-TaS2 or superconducting 2H-NbSe2,bulk 2H-TaSe2 has been a canonical system and a touchstone for modeling the CDW measurement with a less complex phase diagram.In contrast to ordinary semiconductors that have only single-particle excitations,CDW can have collective excitation and carry current in a collective fashion.However,manipulating this collective condensation of these intriguing systems for device applications has not been explored.Here,the CDW-induced collective driven of non-equilibrium carriers in a field-effect transistor has been demonstrated for the sensitive photodetection at the highly-pursuit terahertz band.We show that the 2H-TaSe2-based photodetector exhibits a fast photoresponse,as short as 14 μs,and a responsivity of over 27 V/W at room temperature.The fast response time,relative high responsivity and ease of fabrication of these devices yields a new prospect of exploring CDW condensate in TMDs with the aim of overcoming the existing limitations for a variety of practical applications at THz spectral range.