def METHOD_NAME(self): # calculates coupled plasmon from cavity mode coupled to antenna mode
    e1 = self.wl_to_ev(self.antenna_wl) # antenna mode, around 746nm
    e2 = self.wl_to_ev(self.cavity_wl) # cavity mode
    eo = 0.5*(e1 + e2) - np.sqrt(0.25*(e2 - e1)**2 + 0.11**2) # V=0.09 in NPoMv2 for 5 modes, increase to match
    self.coupled_wl = self.wl_to_ev(eo)