TY  - JOUR
A1  - Jechow, Andreas
A1  - Seefeldt, Michael
A1  - Kurzke, Henning
A1  - Heuer, Axel
A1  - Menzel, Ralf
T1  - Enhanced two-photon excited fluorescence from imaging agents using true thermal light
JF  - Nature photonics
N2  - Two-photon excited fluorescence (TPEF) is a standard technique in modern microscopy(1), but is still affected by photodamage to the probe. It has been proposed that TPEF can be enhanced using entangled photons(2,3), but this has proven challenging. Recently, it was shown that some features of entangled photons can be mimicked with thermal light, which finds application in ghost imaging(4), subwavelength lithography(5) and metrology(6). Here, we use true thermal light from a superluminescent diode to demonstrate TPEF that is enhanced compared to coherent light, using two common fluorophores and luminescent quantum dots, which suit applications in imaging and microscopy. We find that the TPEF rate is directly proportional to the measured(7) degree of second-order coherence, as predicted by theory. Our results show that photon bunching in thermal light can be exploited in two-photon microscopy, with the photon statistic providing a new degree of freedom.
Y1  - 2013
U6  - https://doi.org/10.1038/NPHOTON.2013.271
SN  - 1749-4885
SN  - 1749-4893
VL  - 7
IS  - 12
SP  - 973
EP  - 976
PB  - Nature Publ. Group
CY  - London
ER  -