Lars Samuelson discusses how nanotechnology can provide efficient lighting and solar energy. He argues that nanowire LEDs can overcome issues with conventional LEDs, such as defect densities and inability to produce long wavelengths. Nanowire LEDs allow for virtually dislocation-free material growth and incorporation of more indium for longer wavelengths. Samuelson also discusses how nanotechnology enables highly efficient solar cells for renewable energy production, noting that solar energy received by Earth in one hour exceeds annual global energy consumption.

1. LARS SAMUELSON
NanoLund and Solid State Physics, Lund University, Lund, Sweden
Nanotechnology providing efficient
lighting & solar energy to the world

2. LARS SAMUELSON
NanoLund and Solid State Physics, Lund University, Lund, Sweden
also CSO for QuNano AB, Sol Voltaics AB, Glo AB & Hexagem AB
Nanotechnology providing efficient
lighting & solar energy to the world

3. HERE COMES THE SUN - OUR MODEL SYSTEM FOR AN IDEAL LAMP
providing us with light of a type that our eyes have gotten accustomed to
May I introduce: THE SUN
while also providing the earth with its most abundant energy resource

4. 500300 700 900 (nm)
Text
HERE COMES THE SUN - providing us with light
of a type that our eyes have gotten accustomed to..
HOW CAN SUCH LIGHT SOURCES BE
MADE, MAKING US INDEPENDENT
AND NOT LIMITED TO DAY-
TIME LIFE?
The SUN is extremely hot, over 5500°C
(slightly below 6000K), and it is (luckily
enough) located 150 million km from us.
The SUN provides us with abundant visible
light, with the spectral distribution of the
light governed by its temperature!
Even when the SUN has gone, at night or
in dark spaces, we still need light, prefe-
rably light that still satisfies our eyes.

5. 500300 700 900 (nm)
Alternative 1:
CHALLENGE: Can we make a nice and efficient light
source, here on earth, resembling the solar radiation
in terms of spectral distribution & brightness?
We could use the radiation from
a very hot filament, as in a light-
bulb i.e. an incandescent lamp
HOWEVER, a light-bulb can only be
operated at a temperature of about
2500°C, and then only about 4% of
the emitted light falls in the visible
range of the spectrum!!
This is obviously NOT good from
an energy point of view!

6. 500300 700 900 (nm)
Text
Alternative 2:
CHALLENGE: Can we make a nice and efficient light
source, here on earth, resembling the solar radiation
in terms of spectral distribution & brightness?
We could make three “lamps”, each
producing Red, Green and Blue light
each with extremely high efficiency
Viewed together, these three colors
are perceived as a perfect “white”
light source, mimicking the SUN!

7. THE SUN, AS WELL AS A LIGHT-BULB,
EMITS PHOTONS BECAUSE ELECTRONS
ARE THERMALLY EXCITED TO HIGHER
ENERGY LEVELS, LATER TO RECOMBINE

8. THE SUN, AS WELL AS A LIGHT-BULB,
EMITS PHOTONS BECAUSE ELECTRONS
ARE THERMALLY EXCITED TO HIGHER
ENERGY LEVELS, LATER TO RECOMBINE

9. THE SUN, AS WELL AS A LIGHT-BULB,
EMITS PHOTONS BECAUSE ELECTRONS
ARE THERMALLY EXCITED TO HIGHER
ENERGY LEVELS, LATER TO RECOMBINE

10. THE SUN, AS WELL AS A LIGHT-BULB,
EMITS PHOTONS BECAUSE ELECTRONS
ARE THERMALLY EXCITED TO HIGHER
ENERGY LEVELS, LATER TO RECOMBINE
COULD WE DESIGN A LIGHT-SOURCE
THAT IS NOT BASED ON BEING HOT?

11. By semiconductor nanotechnology
we can build an LED (light-emitting
diode), in which we can electrically
populate energy states that then
will give rise to photon emission!
THE SUN, AS WELL AS A LIGHT-BULB,
EMITS PHOTONS BECAUSE ELECTRONS
ARE THERMALLY EXCITED TO HIGHER
ENERGY LEVELS, LATER TO RECOMBINE
COULD WE DESIGN A LIGHT-SOURCE
THAT IS NOT BASED ON BEING HOT?

12. THE SUN, AS WELL AS A LIGHT-BULB,
EMITS PHOTONS BECAUSE ELECTRONS
ARE THERMALLY EXCITED TO HIGHER
ENERGY LEVELS, LATER TO RECOMBINE
COULD WE DESIGN A LIGHT-SOURCE
THAT IS NOT BASED ON BEING HOT?
By semiconductor nanotechnology
we can build an LED (light-emitting
diode), in which we can electrically
populate energy states that then
will give rise to photon emission!

13. THE SUN, AS WELL AS A LIGHT-BULB,
EMITS PHOTONS BECAUSE ELECTRONS
ARE THERMALLY EXCITED TO HIGHER
ENERGY LEVELS, LATER TO RECOMBINE
COULD WE DESIGN A LIGHT-SOURCE
THAT IS NOT BASED ON BEING HOT?
By semiconductor nanotechnology
we can build an LED (light-emitting
diode), in which we can electrically
populate energy states that then
will give rise to photon emission!

14. THE SUN, AS WELL AS A LIGHT-BULB,
EMITS PHOTONS BECAUSE ELECTRONS
ARE THERMALLY EXCITED TO HIGHER
ENERGY LEVELS, LATER TO RECOMBINE
COULD WE DESIGN A LIGHT-SOURCE
THAT IS NOT BASED ON BEING HOT?
By semiconductor nanotechnology
we can build an LED (light-emitting
diode), in which we can electrically
populate energy states that then
will give rise to photon emission!

15. LET ME TRY TO EXPLAIN HOW THAT IS ACCOMPLISHED
By semiconductor nanotechnology
we can build an LED (light-emitting
diode), in which we can electrically
populate energy states that then
will give rise to photon emission!

16. Semiconductors can be described
as having two energy bands,
- one with (negative) electrons
- and one with (positive) holes
By semiconductor nanotechnology
we can build an LED (light-emitting
diode), in which we can electrically
populate energy states that then
will give rise to photon emission!
LET ME TRY TO EXPLAIN HOW THAT IS ACCOMPLISHED

17. Semiconductors can be described
as having two energy bands,
- one with (negative) electrons
- and one with (positive) holes
In a DIODE, the electrons are
kept on one side (n-side) & the
holes on the other (p-side).
By semiconductor nanotechnology
we can build an LED (light-emitting
diode), in which we can electrically
populate energy states that then
will give rise to photon emission!
LET ME TRY TO EXPLAIN HOW THAT IS ACCOMPLISHED

18. In a DIODE, the electrons are
kept on one side (n-side) & the
holes on the other (p-side).
If a battery is connected, electrons
& holes recombine creating Photons!
+-
By semiconductor nanotechnology
we can build an LED (light-emitting
diode), in which we can electrically
populate energy states that then
will give rise to photon emission!
LET ME TRY TO EXPLAIN HOW THAT IS ACCOMPLISHED
Semiconductors can be described
as having two energy bands,
- one with (negative) electrons
- and one with (positive) holes

19. In a DIODE, the electrons are
kept on one side (n-side) & the
holes on the other (p-side).
If a battery is connected, electrons
& holes recombine creating Photons!
+-
By semiconductor nanotechnology
we can build an LED (light-emitting
diode), in which we can electrically
populate energy states that then
will give rise to photon emission!
LET ME TRY TO EXPLAIN HOW THAT IS ACCOMPLISHED
Semiconductors can be described
as having two energy bands,
- one with (negative) electrons
- and one with (positive) holes

20. In a DIODE, the electrons are
kept on one side (n-side) & the
holes on the other (p-side).
If a battery is connected, electrons
& holes recombine creating Photons!
+-
By semiconductor nanotechnology
we can build an LED (light-emitting
diode), in which we can electrically
populate energy states that then
will give rise to photon emission!
LET ME TRY TO EXPLAIN HOW THAT IS ACCOMPLISHED
Semiconductors can be described
as having two energy bands,
- one with (negative) electrons
- and one with (positive) holes

21. At least 25% of global electricity is spent for Ligh7ng & Displays

22. Le: axis has the units Tlm h/yr (teralumen-hours per year).
Consump7on of Ligh7ng from Candles, Gas, Kerosene
and Electricity in the United Kingdom 1700–2000
Seven Centuries of Energy Services: The Price and Use of Light in the United Kingdom (1300-2000)
Roger Fouquet and Peter J.G. Pearson

23. After J. Tsao et al., The Blue LED Nobel Prize: Historical context, current scientific
understanding, human benefit , Ann. Phys. (Berlin) 527, No. 5–6, A53–A61 (2015)
Evolu7on of light efficiency in the visible

24. The field of making pn-junctions out of GaN has enabled the fabrication
of white LEDs, today slowly taking over much of the lighting sector, SSL.

25. The field of making pn-junctions out of GaN has enabled the fabrication
of white LEDs, today slowly taking over much of the lighting sector, SSL.
It has also (2014) resulted in a Nobel Prize in Physics for the BLUE LED!
” for the inven7on of efficient blue light emiYng diodes, which has enabled bright and energy saving white light sources”
Shuji Nakamura
University of California at Santa
Barbara, USA
Nobelpriset i fysik 2014
Nobelpriset 2014 The Nobel Prize 2014
Isamu Akasaki
Meijo University and Nagoya
University, Japan
Hiroshi Amano
Nagoya University, Nagoya, Japan

26. The field of making pn-junctions out of GaN has enabled the fabrication
of white LEDs, today slowly taking over much of the lighting sector, SSL.
It has also (2014) resulted in a Nobel Prize in Physics for the BLUE LED!

27. Great, so why isn’t this good enough?
This “white” light has low color
qualities and is unable to adjust
to different lighting needs, for
instance in schools.
The field of making pn-junctions out of GaN has enabled the fabrication
of white LEDs, today slowly taking over much of the lighting sector, SSL.

28. The field of making pn-junctions out of GaN has enabled the fabrication
of white LEDs, today slowly taking over much of the lighting sector, SSL.
For other applications,
such as street-lights,
a simple kind of “white”
satisfies the needs.
Ed Ebrahimian,
City of Los Angeles
“Changing our Glow
for Efficiency”
2013 DOE Solid-
State Ligh7ng R&D
Workshop
This “white” light has low color
qualities and is unable to adjust
to different lighting needs, for
instance in schools.
Great, so why isn’t this good enough?

29. The field of making pn-junctions out of GaN has enabled the fabrication
of white LEDs, today slowly taking over much of the lighting sector, SSL.
Human-Centric lighting
can offer ideal spectral
characteristics with a
“blue/cold” character or
with a “warm” character
- with a dynamic control.
This “white” light has low color
qualities and is unable to adjust
to different lighting needs, for
instance in schools.
Great, so why isn’t this good enough?

30. Great. so why isn’t this good enough?
The field of making pn-junctions out of GaN has enabled the fabrication
of white LEDs, today slowly taking over much of the lighting sector, SSL.
Human-Centric lighting
can offer ideal spectral
characteristics with a
“blue/cold” character or
with a “warm” character
- with a dynamic control.
Human-Centric lighting

31. The field of making pn-junctions out of GaN has enabled the fabrication
of white LEDs, today slowly taking over much of the lighting sector, SSL.
Human-Centric lighting
can offer ideal spectral
characteristics with a
“blue/cold” character or
with a “warm” character
- with a dynamic control.
This “white” light has low color
qualities and is unable to adjust
to different lighting needs, for
instance in schools.
Great, so why isn’t this good enough?

32. The field of making pn-junctions out of GaN has enabled the fabrication
of white LEDs, today slowly taking over much of the lighting sector, SSL.
Blue + Phosphors
Blue GaN LED
Green GaN LED
Red GaAs LED
White LightHuman-Centric lighting
can offer ideal spectral
characteristics with a
“blue/cold” character or
with a “warm” character
- with a dynamic control.
This “white” light has low color
qualities and is unable to adjust
to different lighting needs, for
instance in schools.
Great, so why isn’t this good enough?

33. Great, so why isn’t this good enough?
Why do we need novel nanotechnology
approaches to improve things?
We need ultra-bright BLUE, GREEN and RED light to make WHITE

34. Great, so why isn’t this good enough?
Why do we need novel nanotechnology
approaches to improve things?
We need ultra-bright BLUE, GREEN and RED light to make WHITE
The GREEN valley

35. Why do we need novel nanotechnology
approaches to improve things?
1) Today’s GaN (still) has very high defect densities, while
GaN nanowires can be made virtually dislocation-free
GaN nanowires (NWs)
Great, so why isn’t this good enough?

36. Why do we need novel nanotechnology
approaches to improve things?
1) Today’s GaN (still) has very high defect densities, while
GaN nanowires can be made virtually dislocation-free
2) Today’s planar GaN cannot reach long wave-length, due to the
inability to incorporate sufficient amount of In in the InGaN
GaN nanowires (NWs)
Great, so why isn’t this good enough?

37. Great, so why isn’t this good enough?
Why do we need novel nanotechnology
approaches to improve things?
1) Today’s GaN (still) has very high defect densities, while
GaN nanowires can be made virtually dislocation-free
2) Today’s planar GaN cannot reach long wave-length, due to the
inability to incorporate sufficient amount of In in the InGaN
3) Today’s planar GaN LEDs are negatively influenced by built-in
piezo-electric fields that separate electrons and holes in the c-
direction, but nanowire LEDs can be made on non-polar m-planes
GaN nanowires (NWs)

38. In our approach we grow ideal, perfect arrays of GaN nano-
wires by seeding nucleation in ≈100nm holes in a SiNx mask
glō

39. NanoLund and its Solid State Lighting Research Center develops, jointly with Glo AB,
NW-LEDs for highly efficient illumination with very high quality color characteristics
Cathode
Anode
p-spreading contact
glō Monemar, Ohlsson, Gardner and Samuelson,“"Nanowire-based visible
light emitters, present status and outlook", REVIEW Article (2016).

40. First market applications of nanoLEDs:
RGB color addressing of backlit LCD-
screens for smart phones, tablets,
computers, TV-screens etc
glō
Television
Tablet
Desktop PC
Notebook PC Monitor
Naviga7on
Smartphone
Digital Signage

41. Next Generation LED-based Bulbless Luminaires
Bulb-less, free
form luminaires
Bulb-less, luminous
wall coverings
Today’s LED bulbs
will morph into ...
glō

42. Nanotechnology is offering highly efficient &
affordable solar-cells for renewable energy!

43. So - “HERE COMES THE SUN” - AGAIN
Nanotechnology is offering highly efficient &
affordable solar-cells for renewable energy!

44. So - “HERE COMES THE SUN” - AGAIN
TO SAVE THE EARTH AND OFFER THE IDEAL
& ABUNDANT RENEWABLE ENERGY SOURCE!
Nanotechnology is offering highly efficient &
affordable solar-cells for renewable energy!

45. THE 1 000 000 000 000 000 photons/mm2 & sec
corresponds to about 1 kW per m2, which in turn
means that the earth every hour receives as much
solar energy flux as the earth consumes in a year!
So - “HERE COMES THE SUN” - AGAIN
TO SAVE THE EARTH AND OFFER THE IDEAL
& ABUNDANT RENEWABLE ENERGY SOURCE!
Nanotechnology is offering highly efficient &
affordable solar-cells for renewable energy!

46. Annual energy from the sun
Solar is the only solution
Coal
EquivalentStockofEnergySource
Annual
energy use
OilNat. gasUran

47. The red squares represent the area that would be enough for solar power plants to
produce a quantity of electricity consumed by the world today, in Europe (EU-25)
and Germany (De). (Data provided by the German Aerospace Centre (DLR), 2005)
THE 1 000 000 000 000 000 photons/mm2 & sec
corresponds to about 1 kW per m2, which in turn
means that the earth every hour receives as much
solar energy flux as the earth consumes in a year!

48. SO - HOW CAN WE USE NANOTECHNOLOGY TO HARVEST
ENERGY FROM THE SUN AND MAKE IT AVAILABLE TO US?

49. SO - HOW CAN WE USE NANOTECHNOLOGY TO HARVEST
ENERGY FROM THE SUN AND MAKE IT AVAILABLE TO US?
How does Mother
nature harvest sun-
light?

50. How does Mother
nature harvest sun-
light?
Chlorophyll molecules absorb
photons from the sun,
SO - HOW CAN WE USE NANOTECHNOLOGY TO HARVEST
ENERGY FROM THE SUN AND MAKE IT AVAILABLE TO US?

51. SO - HOW CAN WE USE NANOTECHNOLOGY TO HARVEST
ENERGY FROM THE SUN AND MAKE IT AVAILABLE TO US?
How does Mother
nature harvest sun-
light?
Chlorophyll molecules absorb
photons from the sun, creating
electron-hole pairs that very
quickly are separated, giving
rise to creation of biomaterial.

52. SO - HOW CAN WE USE NANOTECHNOLOGY TO HARVEST
ENERGY FROM THE SUN AND MAKE IT AVAILABLE TO US?
How does Mother
nature harvest sun-
light?
Chlorophyll molecules absorb
photons from the sun, creating
electron-hole pairs that very
quickly are separated, giving
rise to creation of biomaterial.

53. In a photovoltaic (PV) solar-cell,
absorption of photons from the
sun leads to creation of electron-
hole pairs that very quickly are
separated by the electric field,
generating electrical power.
SO - HOW CAN WE USE NANOTECHNOLOGY TO HARVEST
ENERGY FROM THE SUN AND MAKE IT AVAILABLE TO US?
How does Mother
nature harvest sun-
light?
Chlorophyll molecules absorb
photons from the sun, creating
electron-hole pairs that very
quickly are separated, giving
rise to creation of biomaterial.

54. In a photovoltaic (PV) solar-cell,
absorption of photons from the
sun leads to creation of electron-
hole pairs that very quickly are
separated by the electric field,
generating electrical power.
SO - HOW CAN WE USE NANOTECHNOLOGY TO HARVEST
ENERGY FROM THE SUN AND MAKE IT AVAILABLE TO US?
How does Mother
nature harvest sun-
light?
Chlorophyll molecules absorb
photons from the sun, creating
electron-hole pairs that very
quickly are separated, giving
rise to creation of biomaterial.

55. In a photovoltaic (PV) solar-cell,
absorption of photons from the
sun leads to creation of electron-
hole pairs that very quickly are
separated by the electric field,
generating electrical power.
SO - HOW CAN WE USE NANOTECHNOLOGY TO HARVEST
ENERGY FROM THE SUN AND MAKE IT AVAILABLE TO US?
How does Mother
nature harvest sun-
light?
Chlorophyll molecules absorb
photons from the sun, creating
electron-hole pairs that very
quickly are separated, giving
rise to creation of biomaterial.

56. In a photovoltaic (PV) solar-cell,
absorption of photons from the
sun leads to creation of electron-
hole pairs that very quickly are
separated by the electric field,
generating electrical power.
SO - HOW CAN WE USE NANOTECHNOLOGY TO HARVEST
ENERGY FROM THE SUN AND MAKE IT AVAILABLE TO US?
How does Mother
nature harvest sun-
light?
Chlorophyll molecules absorb
photons from the sun, creating
electron-hole pairs that very
quickly are separated, giving
rise to creation of biomaterial.

57. LOAD
In a photovoltaic (PV) solar-cell,
absorption of photons from the
sun leads to creation of electron-
hole pairs that very quickly are
separated by the electric field,
generating electrical power.
“BASICALLY SAME MECHANISMS:
NOTHING NEW UNDER THE SUN!”
SO - HOW CAN WE USE NANOTECHNOLOGY TO HARVEST
ENERGY FROM THE SUN AND MAKE IT AVAILABLE TO US?
How does Mother
nature harvest sun-
light?
Chlorophyll molecules absorb
photons from the sun, creating
electron-hole pairs that very
quickly are separated, giving
rise to creation of biomaterial.

58. !

60. Gen 3.5 (Lund Univ.)
Gen 4+ (Sol Voltaics)
23/11/14
Aerotaxy)Gen)4
• Sol)Voltaics’)lab)in)Lund)
• Pre9pilot)produc;on)
• Up)to)six)growth)stages)
• Started)in)October914
Images by Luke Hankin, Sol Voltaics AB
1"µm" 0.5"µm"
“K A Wallenberg Foundation”: “Aerotaxy: a revolutionary new way to grow semiconductor nanowires”

61. By semiconductor
device technology
- and Materials Science for
Nanowires we can now offer:
Nanotechnology providing efficient lighting & solar energy to the world

62. I: efficient and “cold” light
as energy-saving ideal lamps:
Light-emitting diodes, LEDs
+-
By semiconductor
device technology
- and Materials Science for
Nanowires we can now offer:
Nanotechnology providing efficient lighting & solar energy to the world
glō

63. II: efficient harvesting of
the energy from the sun, in:
I: efficient and “cold” light
as energy-saving ideal lamps:
Light-emitting diodes, LEDs Photovoltaic (PV) Solar Cells
+-
LOAD
By semiconductor
device technology
- and Materials Science for
Nanowires we can now offer:
Nanotechnology providing efficient lighting & solar energy to the world
glō

64. Outlook: “NANOSCIENCE FOR THE BENEFIT
OF THE DEVELOPING WORLD”

65. NANOWIRE technology offers unique opportunities for:
Outlook: “NANOSCIENCE FOR THE BENEFIT
OF THE DEVELOPING WORLD”

66. NANOWIRE technology offers unique opportunities for:
Distributed Energy supply via Solar Cells
Outlook: “NANOSCIENCE FOR THE BENEFIT
OF THE DEVELOPING WORLD”

67. NANOWIRE technology offers unique opportunities for:
Distributed Energy supply via Solar Cells
Outlook: “NANOSCIENCE FOR THE BENEFIT
OF THE DEVELOPING WORLD”

68. Distributed Energy supply via Solar Cells
Efficient low-voltage lighting via LEDs
NANOWIRE technology offers unique opportunities for:
Outlook: “NANOSCIENCE FOR THE BENEFIT
OF THE DEVELOPING WORLD”

69. Distributed Energy supply via Solar Cells
Efficient low-voltage lighting via LEDs
Supply of drinkable water via UV-LEDs
NANOWIRE technology offers unique opportunities for:
Outlook: “NANOSCIENCE FOR THE BENEFIT
OF THE DEVELOPING WORLD”

70. Distributed Energy supply via Solar Cells
Efficient low-voltage lighting via LEDs
Supply of drinkable water via UV-LEDs
Health monitoring via Nano-fluidic lab-on-chip
NANOWIRE technology offers unique opportunities for:
PI Jonas
Tegenfeldt
Outlook: “NANOSCIENCE FOR THE BENEFIT
OF THE DEVELOPING WORLD”

71. Distributed Energy supply via Solar Cells
Efficient low-voltage lighting via LEDs
Supply of drinkable water via UV-LEDs
Health monitoring via Nano-fluidic lab-on-chip
NANOWIRE technology offers unique opportunities for:
PI Jonas
Tegenfeldt
Outlook: “NANOSCIENCE FOR THE BENEFIT
OF THE DEVELOPING WORLD”
Northern Europe’s
Materials Science and Nano-Innova7on Center
Science Village
Scandinavia
ProNano Fab
Materials Business
Center
Presently is being planned
how to optimally transform
Key Enabling Technologies
from basic research into
Sustainable Business, via
the creation of ProNano
as a nanotechnology pilot
plant facility for start-ups
and established companies.

72. LET THERE BE LIGHT EMITTING DIODES
and INEXPENSIVE & EFFICIENT SOLAR CELLS
In 10 years:
≈ 1BSEK for
R&D in Glo &
Sol Voltaics
In 15 years:
≈ 1BSEK for
Nanoscience
at Lund Univ.
THANK YOU FOR YOUR ATTENTION!
- with special thanks to George Harrison (Mysty Music) for the music and to Markus Samuelson for guitar picking!