# Quantum dot superluminescent diodes for optical coherence tomography

## Device engineering

Purnima D L Greenwood, David T D Childs, Kenneth Kennedy, Kristian M. Groom, Maxime Hugues, Mark Hopkinson, Richard A. Hogg, Nikola Krstajić, Louise E. Smith, Stephen J. Matcher, Marco Bonesi, Sheila MacNeil, Rod Smallwood

Research output: Contribution to journalArticle

40 Citations (Scopus)

### Abstract

We present a 18 mW fiber-coupled single-mode superluminescent diode with 85 nm bandwidth for application in optical coherence tomography (OCT). First, we describe the effect of quantum dot (QD) growth temperature on optical spectrum and gain, highlighting the need for the optimization of epitaxy for broadband applications. Then, by incorporating this improved material into a multicontact device, we show how bandwidth and power can be controlled. We then go on to show how the spectral shape influences the autocorrelation function, which exhibits a coherence length of <11 $\mu$m, and relative noise is found to be 10 dB lower than that of a thermal source. Finally, we apply the optimum device to OCT of in vivo skin and show the improvement that can be made with higher power, wider bandwidth, and lower noise, respectively.

Original language English 5445054 1015-1022 8 IEEE Journal on Selected Topics in Quantum Electronics 16 4 https://doi.org/10.1109/JSTQE.2009.2038720 Published - Jul 2010

### Fingerprint

Optical tomography
Semiconductor quantum dots
Diodes
tomography
diodes
quantum dots
engineering
bandwidth
Bandwidth
Optical fiber coupling
Growth temperature
Autocorrelation
Epitaxial growth
epitaxy
low noise
autocorrelation
optical spectrum
Skin
optimization

### Keywords

• Optical coherence tomography (OCT)
• quantum dot (QD)
• skin imaging
• superluminescent diodes (SLEDs)

### Cite this

Greenwood, P. D. L., Childs, D. T. D., Kennedy, K., Groom, K. M., Hugues, M., Hopkinson, M., ... Smallwood, R. (2010). Quantum dot superluminescent diodes for optical coherence tomography: Device engineering. IEEE Journal on Selected Topics in Quantum Electronics, 16(4), 1015-1022. [5445054]. https://doi.org/10.1109/JSTQE.2009.2038720
Greenwood, Purnima D L ; Childs, David T D ; Kennedy, Kenneth ; Groom, Kristian M. ; Hugues, Maxime ; Hopkinson, Mark ; Hogg, Richard A. ; Krstajić, Nikola ; Smith, Louise E. ; Matcher, Stephen J. ; Bonesi, Marco ; MacNeil, Sheila ; Smallwood, Rod. / Quantum dot superluminescent diodes for optical coherence tomography : Device engineering. In: IEEE Journal on Selected Topics in Quantum Electronics. 2010 ; Vol. 16, No. 4. pp. 1015-1022.
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abstract = "We present a 18 mW fiber-coupled single-mode superluminescent diode with 85 nm bandwidth for application in optical coherence tomography (OCT). First, we describe the effect of quantum dot (QD) growth temperature on optical spectrum and gain, highlighting the need for the optimization of epitaxy for broadband applications. Then, by incorporating this improved material into a multicontact device, we show how bandwidth and power can be controlled. We then go on to show how the spectral shape influences the autocorrelation function, which exhibits a coherence length of <11 $\mu$m, and relative noise is found to be 10 dB lower than that of a thermal source. Finally, we apply the optimum device to OCT of in vivo skin and show the improvement that can be made with higher power, wider bandwidth, and lower noise, respectively.",
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author = "Greenwood, {Purnima D L} and Childs, {David T D} and Kenneth Kennedy and Groom, {Kristian M.} and Maxime Hugues and Mark Hopkinson and Hogg, {Richard A.} and Nikola Krstajić and Smith, {Louise E.} and Matcher, {Stephen J.} and Marco Bonesi and Sheila MacNeil and Rod Smallwood",
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Greenwood, PDL, Childs, DTD, Kennedy, K, Groom, KM, Hugues, M, Hopkinson, M, Hogg, RA, Krstajić, N, Smith, LE, Matcher, SJ, Bonesi, M, MacNeil, S & Smallwood, R 2010, 'Quantum dot superluminescent diodes for optical coherence tomography: Device engineering', IEEE Journal on Selected Topics in Quantum Electronics, vol. 16, no. 4, 5445054, pp. 1015-1022. https://doi.org/10.1109/JSTQE.2009.2038720

Quantum dot superluminescent diodes for optical coherence tomography : Device engineering. / Greenwood, Purnima D L; Childs, David T D; Kennedy, Kenneth; Groom, Kristian M.; Hugues, Maxime; Hopkinson, Mark; Hogg, Richard A.; Krstajić, Nikola; Smith, Louise E.; Matcher, Stephen J.; Bonesi, Marco; MacNeil, Sheila; Smallwood, Rod.

In: IEEE Journal on Selected Topics in Quantum Electronics, Vol. 16, No. 4, 5445054, 07.2010, p. 1015-1022.

Research output: Contribution to journalArticle

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T1 - Quantum dot superluminescent diodes for optical coherence tomography

T2 - Device engineering

AU - Greenwood, Purnima D L

AU - Childs, David T D

AU - Kennedy, Kenneth

AU - Groom, Kristian M.

AU - Hugues, Maxime

AU - Hopkinson, Mark

AU - Hogg, Richard A.

AU - Krstajić, Nikola

AU - Smith, Louise E.

AU - Matcher, Stephen J.

AU - Bonesi, Marco

AU - MacNeil, Sheila

AU - Smallwood, Rod

PY - 2010/7

Y1 - 2010/7

N2 - We present a 18 mW fiber-coupled single-mode superluminescent diode with 85 nm bandwidth for application in optical coherence tomography (OCT). First, we describe the effect of quantum dot (QD) growth temperature on optical spectrum and gain, highlighting the need for the optimization of epitaxy for broadband applications. Then, by incorporating this improved material into a multicontact device, we show how bandwidth and power can be controlled. We then go on to show how the spectral shape influences the autocorrelation function, which exhibits a coherence length of <11 $\mu$m, and relative noise is found to be 10 dB lower than that of a thermal source. Finally, we apply the optimum device to OCT of in vivo skin and show the improvement that can be made with higher power, wider bandwidth, and lower noise, respectively.

AB - We present a 18 mW fiber-coupled single-mode superluminescent diode with 85 nm bandwidth for application in optical coherence tomography (OCT). First, we describe the effect of quantum dot (QD) growth temperature on optical spectrum and gain, highlighting the need for the optimization of epitaxy for broadband applications. Then, by incorporating this improved material into a multicontact device, we show how bandwidth and power can be controlled. We then go on to show how the spectral shape influences the autocorrelation function, which exhibits a coherence length of <11 $\mu$m, and relative noise is found to be 10 dB lower than that of a thermal source. Finally, we apply the optimum device to OCT of in vivo skin and show the improvement that can be made with higher power, wider bandwidth, and lower noise, respectively.

KW - Optical coherence tomography (OCT)

KW - quantum dot (QD)

KW - skin imaging

KW - superluminescent diodes (SLEDs)

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