An electron of mass m with an initial velocity \(\overrightarrow{V} = V_0 \hat{i} (V_0 \gt 0)\) enters an electric field \(\overrightarrow{E} = -E_0 \;\hat{i} (E_0=constant \gt 0)\) at t = 0. If \(\lambda_0\) is its de-Broglie wavelength initially, then its de-Broglie wavelength at time t is