A light detection and ranging (LIDAR) apparatus includes an optical circuit including a laser source configured to emit a laser beam, a beam separator operatively coupled to the laser source, the beam separator configured to separate the laser beam propagated towards a target, a first optical amplifier coupled to the beam separator, the first optical amplifier configured to receive a return laser beam reflected from the target in a return path and amplify the return laser beam to output an amplified return laser beam, and an optical component operatively coupled to the first optical amplifier, the optical component configured to output a current based on the amplified return laser beam.