Enhanced Valley Zeeman Splitting in Fe-Doped Monolayer MoS₂

Area of Science:

• Condensed Matter Physics
• Materials Science
• Spintronics

Background:

• The Zeeman effect enables magnetic manipulation of spin.
• Valley Zeeman splitting in 2D transition metal dichalcogenides (TMDs) was previously limited to low temperatures.
• Controlling valley pseudospins at room temperature is crucial for practical applications.

Purpose of the Study:

• To demonstrate magnetic manipulation of valley Zeeman splitting at room temperature in a 2D material.
• To investigate the effect of magnetic doping on valley Zeeman splitting.
• To explore the underlying mechanisms for enhanced valley splitting.

Main Methods:

• Chemical Vapor Deposition (CVD) growth of Fe-doped MoS2 monolayer.
• Experimental measurement of valley Zeeman splitting at 300 K and 10 K.
• Theoretical calculations to understand the magnetic interactions and orbital hybridization.

Main Results:

• Unambiguous magnetic manipulation of valley Zeeman splitting achieved at 300 K (g_eff = -6.4) and 10 K (g_eff = -11).
• Effective Landé g_eff factor tuned up to -20.7 with increasing Fe concentration, a ~5-fold enhancement over undoped MoS2.
• Enhanced splitting attributed to Heisenberg exchange interaction between Fe 3d electrons and MoS2 via d-orbital hybridization.

Conclusions:

• Fe-doped MoS2 enables magnetic control of valley Zeeman splitting at room temperature.
• Magnetic doping significantly enhances the effective Landé g_eff factor.
• The findings pave the way for spintronic devices utilizing valley pseudospins at ambient conditions.