International Journal of Modern Physics B

Steady-state light amplification in a three-level ladder-type graphene ensemble under Landau quantization

Jianming Meng, Longjian Guo, Yanjuan Tian

Published May 23, 2025• 0 citations

Abstract

In this study, we explore the interplay of laser beams with a graphene sample in a ladder configuration under various conditions of coherent and incoherent fields. We investigate how these interactions influence absorption and amplification, focusing on the effects of control field detuning, incoherent pumping, and varying decay rates. We first analyze the system’s response under resonance conditions, revealing symmetric gain profiles with distinct gain dips. As incoherent pumping is introduced, we observe a reduction in gain, highlighting the role of population transfer in modulating amplification. Furthermore, we examine the impact of control field detuning, which disrupts the symmetry of the gain profile and shifts the gain dip to nonzero detuning values. Additionally, by varying the decay rates of the intermediate state, we find that higher decay rates lead to asymmetric gain profiles and reduced amplification. Importantly, the gain observed in these graphene systems is inversionless. Our results provide insights into the tunability of graphene’s optical properties, demonstrating its potential for advanced optoelectronic applications that demand exact manipulation of light and material interactions.

DOI: 10.1142/s021797922550184x

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