Saxena Shailendra K, Yogi Priyanka, Mishra Suryakant, Rai Hari Mohan, Mishra Vikash, Warshi M Kamal, Roy Swarup, Mondal Puspen, Sagdeo Pankaj R, Kumar Rajesh
Material Research Laboratory, Discipline of Physics & MEMS, Indian Institute of Technology Indore, Simrol-453552, India.
Phys Chem Chem Phys. 2017 Dec 6;19(47):31788-31795. doi: 10.1039/c7cp04836j.
Fano resonance is reported here to be playing a dual role by amplifying or compensating for the quantum confinement effect induced asymmetry in Raman line-shape in silicon (Si) nanowires (NWs) obtained from heavily doped n- and p-type Si wafers respectively. The compensatory nature results in a near symmetric Raman line-shape from heavily doped p-type Si nanowires (NWs) as both the components almost cancel each other. On the other hand, the expected asymmetry, rather with enhancement, has been observed from heavily doped n-type SiNWs. Such a system (p- & n-) dependent Raman line-shape study has been carried out by theoretical line-shape analysis followed by experimental validation through suitably designed experiments. A dual role of Fano resonance in n- and p-type nano systems has been observed to modulate Raman spectra differently and reconcile accordingly to enhance and cease the Raman spectral asymmetry respectively. The present analysis will enable one to be more careful while analyzing a symmetric Raman line-shape from semiconductor nanostructures.
据报道，法诺共振在这里发挥着双重作用，它分别对由重掺杂n型和p型硅晶片获得的硅（Si）纳米线（NWs）中拉曼线形中量子限制效应引起的不对称性进行放大或补偿。这种补偿性质导致重掺杂p型硅纳米线（NWs）的拉曼线形接近对称，因为两个分量几乎相互抵消。另一方面，从重掺杂n型硅纳米线中观察到了预期的不对称性，且伴有增强。通过理论线形分析，随后通过适当设计的实验进行实验验证，开展了这种依赖于系统（p型和n型）的拉曼线形研究。已观察到法诺共振在n型和p型纳米系统中的双重作用，分别以不同方式调制拉曼光谱，并相应地进行调节，以增强和消除拉曼光谱的不对称性。本分析将使人们在分析半导体纳米结构的对称拉曼线形时更加谨慎。
