| 摘要 |
<p>A method of modulating a multisection quantum dot laser comprising varying a tuning current between inactive an active ranges so that the laser does not lase when the tuning current is the inactive range. Varying the tuning current may result in duobinary modulation. The laser may comprise at least first and second sections 8, 9, each comprising a semiconductor substrate comprising p and n type layers and a quantum dot layer sandwiched therebetween; the semiconductor substrate comprising a back electrical contact in electrical contact with one of the p and n type layers and a tuning electrical contact in electrical contact with the other of the p and n type layers; the quantum dot layers of the first and second sections being portion of the same quantum dot layer 12 forming a laser cavity. Each tuning electrical contact 13, 14 and back electrical contact pair may be connected such that both sections are forward biased.</p> |
