Observation of the triplet exciton in EuS-coated single-walled nanotubes.
نویسندگان
چکیده
Photon absorption by carbon nanotubes creates bound electron-hole pairs called excitons, which can exist in spin-polarized triplet or spin-unpolarized singlet configurations. Triplet excitons are optically inactive owing to the weak spin-orbit coupling in nanotubes. This prevents the optical injection of electron spin into nanotubes for spintronic applications and limits the efficiency of photocurrent generation. Here, we show that it is possible to optically excite the triplet exciton by using a ferromagnetic semiconductor as a spin filter to mix the singlet and triplet excitons. The triplet contribution to the photocurrent is detected, representing the first direct evidence of the triplet exciton in carbon nanotubes.
منابع مشابه
Title Observation of exciton-phonon sideband in individual metallic single-walled carbon nanotubes
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ورودعنوان ژورنال:
- Nature nanotechnology
دوره 4 7 شماره
صفحات -
تاریخ انتشار 2009