Tunneling-induced quantum interference experienced by an incident probe in the asymmetric double AlGaAs/GaAs quantum well (QW) structure can be modulated by means of an external control light beam and the tunable coupling strengths of resonant tunneling. These phenomena can be exploited to devise a novel intracavity medium to control Goos-Hänchen (GH) shifts of a mid-infrared probe beam incident on a cavity. For a suitably designed QW structure, our results show that maximum negative shift of 2.62 mm and positive shift of 0.56 mm are achievable for GH shifts in the reflected and transmitted light. The Goos-Hänchen (GH) effect happens when a linearly polarized light undergoes a small lateral shift for the totally internal reflection from the interface of two different media [1]. The observation by Goos and Hänchen in 1947 has attracted considerable interest because of a variety of applications in optical heterodyne sensing and precision measurement, such as refractive index, displacement, temperature, and film thickness [2][3][4]. Interesting proposals toward the control or enhancement of GH shift have already been proposed to have negative and positive GH shifts [5][6][7][8][9].In this Letter, we present a proof-of-principle investigation by demonstrating that tunneling-induced quantum interference in a semiconductor quantum well (QW) structure can be exploited to provide an efficient new mechanism for enhancing and controlling GH shift in the reflected and transmitted light. Compared to the scenario when the control beam is off, the GH shift can be reduced significantly in the presence of an external control beam. The different responses depend on whether the tunneling-induced interference is quenched or well developed. Quantum interference-based phenomena, such as electromagnetically induced transparency (EIT) [10,11], lasing without population inversion [12,13], and Raman gain process [14,15] have attracted considerable attention. Simultaneously, these phenomena also are extended to a variety of applications [15,16]. Different from the mechanism of controlling GH shift based on photon-induced changes of the medium refractive index via coherent control beam [5][6][7][8][9], the mechanism of control GH shift is achieved here as a result of the tunneling-induced quantum interference [17][18][19][20][21][22][23].The schematic of a weak probe light incident upon a cavity containing semiconductor QWs in the configuration of four subbands is shown in Fig. 1. The cavity consists of three layers of materials: two nonmagnetic dielectric slabs ε 1 with the same thickness d 1 and a QW medium ε 2 with thickness d 2 ; see Fig. 1(a). The asymmetric QW (intracavity medium) structure with the relevant conduction band levels and wave function is shown in Fig. 1(b), which can be grown in the sequence from left to right. A thick Al 0.4 Ga 0.6 As barrier is followed by a Al 0.16 Ga 0.84 As shallow well (6.8 nm) that is separated from the GaAs deep well (7.7 nm) on the right by a Al 0.4 Ga 0.6 As potential barrier (3.0 nm). Subseq...