44
2 Entering a Two-Dimensional Materials World
Fig. 2.15 Three early examples of microcavity lasers based on 2D-semiconductor gain regions. Top
left box: A photonic-crystal cavity with monolayer, also see Fig. 2.3. Reproduced with permission.
[70] Copyright 2015 Springer Nature. Top right box: Sketch of a whispering-gallery-mode laser
based on a processed Si 3 N 4 microdisk resonator on silicon substrate (left) and corresponding SEM
image of the actual device (right). The 2D semiconductor deposited onto the disk is capped by a
transparent medium (HSQ: hydrogen silsesquioxane) for an optimised out-of-plane mode distribution profile, i.e. for the maximisation of the laser mode’s electric field in the plane of the 2D gain
medium. Reproduced with permission. [72] Copyright 2015 Springer Nature. Bottom box: a Sketch
of a microlaser based on a combination of two whispering-gallery-mode resonators (a sphere on a
disk) with monolayer gain material deposited onto the disk. b Top-view SEM image of the device.
c Calculated mode pattern in a cross-sectional view on the sphere (circular part) attached to the
disk (flat part). As this image shows, this approach allows to maximise the laser mode’s electric
field at the position of the gain material in-between the two attached cavities at the intersection
owing to the joint mode pattern. Moreover, owing to the different free-spectral ranges (FSR) of the
two resonators, a strong mode reduction is achieved, since the standing-wave pattern must match
both resonator conditions. Reproduced with permission. [71] Copyright 2015 American Chemical
Society
References
1. K.S. Novoselov, A.K. Geim, S.V. Morozov, D. Jiang, Y. Zhang, S.V. Dubonos, I.V. Grigorieva,
A.A. Firsov, Electric field effect in atomically thin carbon films. Science 306, 666–669 (2004)
2. K.S. Novoselov, D. Jiang, F. Schedin, T.J. Booth, V.V. Khotkevich, S.V. Morozov, A.K. Geim,
Two-dimensional atomic crystals. Proc. Natl. Acad. Sci. 102, 10451–10453 (2005)
3. K.F. Mak, C. Lee, J. Hone, J. Shan, T.F. Heinz, Atomically thin MoS 2 : a new direct-gap
semiconductor. Phys. Rev. Lett. 105, 136805 (2010)
4. A. Splendiani, L. Sun, Y. Zhang, T. Li, J. Kim, C.-Y. Chim, G. Galli, F. Wang, Emerging
photoluminescence in monolayer MoS 2 . Nano Lett. 10, 1271–1275 (2010)
5. Z. Lin, A. McCreary, N. Briggs, S. Subramanian, K. Zhang, Y. Sun, X. Li, N. J. Borys,
H. Yuan, S. K. Fullerton-Shirey, A. Chernikov, H. Zhao, S. McDonnell, A.M. Lindenberg,
K. Xiao, B.J. LeRoy, M. Drndi´ c, J.C.M. Hwang, J. Park, M. Chhowalla, R.E. Schaak, A. Javey,
M.C. Hersam, J. Robinson, M. Terrones, 2D materials advances: from large scale synthesis and
2 Entering a Two-Dimensional Materials World
Fig. 2.15 Three early examples of microcavity lasers based on 2D-semiconductor gain regions. Top
left box: A photonic-crystal cavity with monolayer, also see Fig. 2.3. Reproduced with permission.
[70] Copyright 2015 Springer Nature. Top right box: Sketch of a whispering-gallery-mode laser
based on a processed Si 3 N 4 microdisk resonator on silicon substrate (left) and corresponding SEM
image of the actual device (right). The 2D semiconductor deposited onto the disk is capped by a
transparent medium (HSQ: hydrogen silsesquioxane) for an optimised out-of-plane mode distribution profile, i.e. for the maximisation of the laser mode’s electric field in the plane of the 2D gain
medium. Reproduced with permission. [72] Copyright 2015 Springer Nature. Bottom box: a Sketch
of a microlaser based on a combination of two whispering-gallery-mode resonators (a sphere on a
disk) with monolayer gain material deposited onto the disk. b Top-view SEM image of the device.
c Calculated mode pattern in a cross-sectional view on the sphere (circular part) attached to the
disk (flat part). As this image shows, this approach allows to maximise the laser mode’s electric
field at the position of the gain material in-between the two attached cavities at the intersection
owing to the joint mode pattern. Moreover, owing to the different free-spectral ranges (FSR) of the
two resonators, a strong mode reduction is achieved, since the standing-wave pattern must match
both resonator conditions. Reproduced with permission. [71] Copyright 2015 American Chemical
Society
References
1. K.S. Novoselov, A.K. Geim, S.V. Morozov, D. Jiang, Y. Zhang, S.V. Dubonos, I.V. Grigorieva,
A.A. Firsov, Electric field effect in atomically thin carbon films. Science 306, 666–669 (2004)
2. K.S. Novoselov, D. Jiang, F. Schedin, T.J. Booth, V.V. Khotkevich, S.V. Morozov, A.K. Geim,
Two-dimensional atomic crystals. Proc. Natl. Acad. Sci. 102, 10451–10453 (2005)
3. K.F. Mak, C. Lee, J. Hone, J. Shan, T.F. Heinz, Atomically thin MoS 2 : a new direct-gap
semiconductor. Phys. Rev. Lett. 105, 136805 (2010)
4. A. Splendiani, L. Sun, Y. Zhang, T. Li, J. Kim, C.-Y. Chim, G. Galli, F. Wang, Emerging
photoluminescence in monolayer MoS 2 . Nano Lett. 10, 1271–1275 (2010)
5. Z. Lin, A. McCreary, N. Briggs, S. Subramanian, K. Zhang, Y. Sun, X. Li, N. J. Borys,
H. Yuan, S. K. Fullerton-Shirey, A. Chernikov, H. Zhao, S. McDonnell, A.M. Lindenberg,
K. Xiao, B.J. LeRoy, M. Drndi´ c, J.C.M. Hwang, J. Park, M. Chhowalla, R.E. Schaak, A. Javey,
M.C. Hersam, J. Robinson, M. Terrones, 2D materials advances: from large scale synthesis and