logo

korean english

게시판

Home > 게시판 > 세미나

아래와 같이 콜로퀴움을 개최하오니 많이 참석해 주시기 바랍니다.
420분부터 제1과학관 31214 e+강의실에서 다과를 준비하오니 많은 참석 부탁드립니다

 

아 래

 

제목Contribution of Internal and Surface Traps to Blinking Statistics in Colloidal Quantum Dots

 

연사: 국   양 교수님 (서울대학교 자연과학대학 물리천문학부)

                                        

일시: 2014년 5월 7() 오후4:30

 

장소: 1과학관 31214  첨단e+강의실

 

초록: Colloidal quantum dots (QDs) have been successfully developed into nanoscale light sources with variable wavelength. However, fluorescence intermittency (FI), also known as photoluminescence blinking, remains a major problem. FI was first observed seventeen years ago in a QD1. It is now thought that trap states in the QD play a major role in the origin of FI. However, proposed microscopic models still give contradictory predictions, mainly due to the lack of information on the spatial and energetic distribution of traps. We observed internal and surface trap states for the first time using scanning tunneling microscopy and spectroscopy. Internal defects induce tens to hundreds of midgap electronic states within every QD. Surface traps appear as charged quantum islands at some ligand molecules. We found that trapping and detrapping dynamics among internal and surfaces traps are important for understanding FI statistics. By performing a Monte Carlo simulation that includes the measured spatial and energetic distribution of the internal and the surface traps, we demonstrate the characteristic power-law statistics of FI. Two types of FI dynamics observed in a recent spectroelectrochemistry experiment2 can also be successfully explained with our internal-surface trap-distribution model. We anticipate this observation to become a corner stone for the complete elimination of FI.

 

[1] A. L. Efros, M. Rosen, Phys. Rev. Lett. 78, 1110 (1997).

[2] C. Galland, Y. Ghosh, A. Steinbrück, M. Sykora, J.A. Hollingsworth, V.I. Klimov, H. Htoon. Nature 479, 203–207 (2011).

 

 

번호 제목 날짜 조회 수
공지 <12/8(Thu.) 11:00am>노벨상 소개 강연 - 2016년 노벨 물리학상: 위상 응집 물리의 탄생 2016.11.28 1056199
262 <11/23> Hot/Dense QCD 2007.11.16 86203
261 <3/12> Where, when and how atomic nuclei were cooked in universe? 2014.03.07 86311
260 <7월27일>Correlated topological phases in 3D complex oxides via Green's functions 2012.07.27 86368
259 <Sep. 9(Wed.) 4:30 PM> Electronic structures of strongly-correlated systems 2015.09.03 86392
258 <10/17> The Interface Induced Magnetism 2012.10.11 86513
257 <5/8>Recent trend of thin film battery 2009.05.06 86604
256 <7/21> Next generation cryogenic free 1.5T MgB2-magnet based MRI 2010.07.20 86657
255 <11/23> How statistical physics contributes to Internet world: perspectives, methods and applications 2011.11.15 86673
254 <3/16> Inelastic X-ray Scattering: past, present, and the future 2011.03.10 86791
253 2015학년도 1학기 콜로퀴움 일정 file 2015.02.27 86823
252 <5/16> superconformal index with line operators and domain walls 2012.05.14 86904
251 <May.16(Wed.) 4:30 PM> Single crystal growth of metal film and metal oxide film on different substrates and their various applications 2018.05.09 87074
250 2011학년도 2학기 콜로퀴움 일정 안내 2011.08.22 87096
» <5/7> Contribution of Internal and Surface Traps to Blinking Statistics in Colloidal Quantum Dots 2014.04.30 87258
248 <8/7> Scotch tape and spectroscopy: probing and manipulating the surface of a topological insulator 2012.07.27 87408
247 <12/14> Breakup-Fusion and Knockout-Fusion Approach to Pre-Equilibrium Processes 2009.12.11 87535
246 <4/16>같은 곳을 바라보는 다른 시선 2010.04.09 87851
245 <6/9> Status and Prospects of Big Science in Korea 2006.06.05 87855
244 <4/3>Enhanced emission rate from a single quantum well using surface plasmon 2009.03.31 87898
243 <Oct.30(Wed.)> 왼손과 오른손, 기본 입자와 끈 2019.10.24 88066